Compounds having benzoxazole ring structure and organic electroluminescent element

Abstract

The object of the present invention is to provide an organic compound having excellent characteristics, excellent electron injection and transport performance, hole blocking ability, and high stability in a thin film state as a material for a high-efficiency and high-durability organic EL element, and further to use the compound to provide a high-efficiency and high-durability organic EL element. The present invention focuses on the fact that the nitrogen atom of the electron-affinity benzoxazole ring structure has the ability to coordinate with metals and has excellent heat resistance, and various compounds having a benzoxazole ring structure are designed and chemically synthesized. Organic EL elements are trial-produced using these compounds, and the characteristics are evaluated. As a result, it is found that an organic EL element having excellent characteristics can be obtained by using a compound having a specific benzoxazole ring structure.

Description

Technical Field

[0001] The present invention relates to a compound and an organic electroluminescent element (hereinafter referred to as an organic EL element) as a self-luminous element suitable for various display devices, and more particularly to a compound having a benzoxazole ring structure and an organic EL element using the compound. Background Art

[0002] Organic EL elements are self-luminous elements and therefore are brighter and more visible than liquid crystal elements, and can provide clear displays, and therefore are being actively studied.

[0003] In 1987, CW Tang and others from Eastman Kodak developed a stacked structure element that assigned various functions to each material, making the organic EL element using organic materials a practical element. They stacked a phosphor that can transport electrons and an organic substance that can transport holes, injected the charges of both into the phosphor layer to make it emit light, and thus obtained 1000 cd / m at a voltage of less than 10V. 2 The above high brightness (for example, refer to Patent Document 1 and Patent Document 2).

[0004] So far, a large number of improvements have been made to make organic EL elements practical, and the various functions of the stacked structure have been further subdivided. An electroluminescent element in which an anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a cathode are sequentially arranged on a substrate has been adopted to achieve high efficiency and durability (for example, refer to non-patent document 1).

[0005] In order to further improve the luminous efficiency, attempts have been made to utilize triplet excitons and to study the use of phosphorescent compounds (see, for example, Non-Patent Document 2).

[0006] Furthermore, devices utilizing light emission using thermally activated delayed fluorescence (TADF) have also been developed. In 2011, Adachi et al. of Kyushu University achieved an external quantum efficiency of 5.3% using a device using a thermally activated delayed fluorescence material (see, for example, Non-Patent Document 3).

[0007] The light-emitting layer can also be made by doping a fluorescent compound, a phosphorescent compound, or a material emitting delayed fluorescence into a charge transporting compound generally referred to as a host material. As described in the above-mentioned non-patent document, the selection of organic materials in an organic EL element has a great influence on various characteristics of the element, such as efficiency and durability (for example, see non-patent document 2).

[0008] In an organic EL element, the charge injected from the two electrodes is compounded in the light-emitting layer to obtain light emission, and how to efficiently deliver the two charges of holes and electrons to the light-emitting layer is important. Therefore, it is necessary to improve the probability of holes and electrons being compounded in the light-emitting layer by improving electron injectability and increasing its mobility. That is, the holes transmitted from the anode side are enclosed in the light-emitting layer to prevent the degradation of the electron transport layer. In addition, the excitons generated in the light-emitting layer are enclosed, so that a compound environment can be further made, and high-efficiency light emission can be obtained. Therefore, the function played by the electron transport material is important, and it is sought that the electron transport material has high electron injectability, large electron mobility, high hole blocking property, and high durability for holes.

[0009] In addition, regarding the life of the element, the heat resistance and amorphism of the material are also important. For materials with low heat resistance, due to the heat generated when the element is driven, thermal decomposition and material degradation occur even at low temperatures. For materials with low amorphism, thin film crystallization occurs even in a short time, and the element deteriorates. Therefore, the materials used are required to have high heat resistance and good amorphism.

[0010] Tris(8-hydroxyquinoline)aluminum (hereinafter referred to as Alq3), which is a representative light-emitting material, is generally used as an electron transport material, but electron migration is slow and its work function is 5.6 eV, so its hole blocking performance is not sufficient.

[0011] As a compound for improving properties such as electron injection and mobility, a compound having a benzotriazole structure has been proposed (e.g., Patent Document 3). For components using these compounds in electron transport layers, although the luminous efficiency is improved, it is not sufficient, and further low driving voltage and further high luminous efficiency are required.

[0012] In addition, 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (hereinafter referred to as TAZ) has been proposed as an electron transport material having excellent hole-blocking properties (see, for example, Patent Document 4).

[0013] TAZ has a work function of 6.6 eV and a high hole-blocking ability. Therefore, it is used as an electron-transporting hole-blocking layer stacked on the cathode side of a fluorescent light-emitting layer or a phosphorescent light-emitting layer produced by vacuum evaporation or coating, which helps to improve the efficiency of organic EL elements (see, for example, non-patent document 4).

[0014] However, low electron transport properties are a major problem in TAZ, and it is necessary to combine it with an electron transport material having a higher electron transport property to produce an organic EL element (see, for example, Non-Patent Document 5).

[0015] In addition, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), which is known as an electron transport material, has a work function of 6.7 eV and a high hole blocking ability, but its glass transition temperature (Tg) is as low as 83°C, so it lacks thin film stability and cannot be said to fully function as a hole blocking layer.

[0016] All materials have insufficient film stability or insufficient hole blocking function. In order to improve the device characteristics of organic EL devices, organic compounds with excellent electron injection and transport performance and hole blocking ability and high stability in a thin film state are sought.

[0017] Prior art literature

[0018] Patent Literature

[0019] Patent document 1: US5792557

[0020] Patent document 2: US5639914

[0021] Patent document 3: US9123897

[0022] Patent document 4: US5869199

[0023] Patent Document 5: US8735597

[0024] Patent Document 6: US9802961

[0025] Patent Document 7: EP2684932

[0026] Patent document 8: US9199966

[0027] Patent document 9: US6878469

[0028] Non-patent literature

[0029] Non-patent document 1: Proceedings of the 9th Seminar of the Society of Applied Physics, pp. 55-61 (2001)

[0030] Non-patent document 2: Proceedings of the 9th Seminar of the Society of Applied Physics, pp. 23-31 (2001)

[0031] Non-patent document 3: Appl. Phys. Lett., 98, 083302 (2011)

[0032] Non-patent document 4: 50th Applied Physics Society Joint Lecture Conference 28p-A-6 Lecture Draft Collection, p. 1413 (2003)

[0033] Non-patent document 5: Journal of the Organic Molecular and Bioelectronics Section of the Japanese Society of Applied Physics, Vol. 11, No. 1, pp. 13-19 (2000)

[0034] Non-patent document 6: J.Org.chcm., 71, 1802 (2006)

[0035] Non-patent document 7: J.Org.chcm., 79, 6310 (2014) Summary of the invention

[0036] The object of the present invention is to provide an organic compound having excellent properties such as excellent electron injection and transport performance, hole blocking ability, and high stability in a thin film state as a material for a high-efficiency and high-durability organic EL element, and further to provide a high-efficiency and high-durability organic EL element using the compound.

[0037] The physical properties that the organic compound provided by the present invention should have include (1) good electron injection properties; (2) high electron mobility; (3) excellent hole blocking ability; (4) stable thin film state; (5) excellent heat resistance. In addition, the physical properties that the organic EL element provided by the present invention should have include (1) high luminous efficiency and power efficiency; (2) low luminous start voltage; (3) low practical driving voltage; and (4) long life.

[0038] Therefore, in order to achieve the above-mentioned purpose, the present inventors focused on the electron affinity of the benzoxazole ring, the ability of the nitrogen atom to coordinate with the metal, and the excellent heat resistance, designed various compounds having a benzoxazole ring structure and chemically synthesized them, used these compounds to trial-produce organic EL devices, and conducted in-depth evaluation of their properties. As a result, the present invention was completed.

[0039] 1) That is, the present invention is a compound represented by the following general formula (a-1) and having a benzoxazole ring structure.

[0040] [Chemistry 1]

[0041]

[0042] (In the formula, R may be the same as or different from each other, and represents a group represented by the following structural formula (b-1), a hydrogen atom, a deuterium atom, a fluorine atom, a chlorine atom, a cyano group, a nitro group, a trimethylsilyl group, a triphenylsilyl group, a diphenylphosphinyl group, a diphenylphosphinyl group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent, a cycloalkyl group having 5 to 10 carbon atoms which may have a substituent, a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent, a linear or branched alkoxy group having 1 to 6 carbon atoms which may have a substituent, or a cycloalkoxy group having 5 to 10 carbon atoms which may have a substituent.

[0043] X represents an oxygen atom or a sulfur atom.

[0044] Y may be the same as or different from each other, and represents a carbon atom or a nitrogen atom having R.

[0045] However, at least one R is a group represented by the following structural formula (b-1).

[0046] [Chemistry 2]

[0047] ----L1-L2-(CN) n(b-1)

[0048] (wherein, L1 and L2 may be the same as or different from each other and represent a single bond, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, or a substituted or unsubstituted condensed polycyclic aromatic group.

[0049] n is an integer of 1 or 2.

[0050] The dotted line indicates the bonding site.)

[0051] 2) In addition, the present invention is the compound having a benzoxazole ring structure as described in 1) above, which is represented by the following general formula (a-2).

[0052] [Chemistry 3]

[0053]

[0054] (In the formula, R and Y have the same meanings as in the above general formula (a-1).)

[0055] 3) In addition, the present invention is the compound having a benzoxazole ring structure as described in 2) above, which is represented by the following general formula (a-3).

[0056] [Chemistry 4]

[0057]

[0058] (In the formula, R has the same meaning as in the above general formula (a-1).)

[0059] 4) In addition, the present invention is the compound having a benzoxazole ring structure as described in 3) above, which is represented by the following general formula (a-4).

[0060] [Chemistry 5]

[0061]

[0062] (In the formula, R has the same meaning as in the above general formula (a-1).)

[0063] 5) In addition, the present invention is the compound having a benzoxazole ring structure as described in 4) above, which is represented by the following general formula (a-5).

[0064] [Chemistry 6]

[0065]

[0066] (In the formula, R has the same meaning as in the above general formula (a-1).)

[0067] 6) In addition, the present invention is the compound having a benzoxazole ring structure as described in 1) above, which is represented by the following general formula (a-6).

[0068] [Chemistry 7]

[0069]

[0070] (In the formula, R has the same meaning as in the above general formula (a-1).)

[0071] 7) In addition, the present invention is the compound having a benzoxazole ring structure as described in 6) above, which is represented by the following general formula (a-7).

[0072] [Chemistry 8]

[0073]

[0074] (In the formula, R has the same meaning as in the above general formula (a-1).)

[0075] 8) In addition, the present invention is a compound having a benzoxazole ring structure as described in 1) to 7) above, wherein n in the above structural formula (b-1) is an integer of 1.

[0076] 9) In addition, the present invention is a compound having a benzoxazole ring structure as described in 1) to 8) above, wherein L2 in the above structural formula (b-1) is a substituted or unsubstituted phenylene group, or a substituted or unsubstituted biphenylene group.

[0077] 10) In addition, the present invention is an organic EL element having a pair of electrodes and at least one organic layer sandwiched therebetween, wherein the organic layer comprises at least one organic layer using the compound having a benzoxazole ring structure described in any one of 1) to 9).

[0078] 11) In addition, the present invention is the organic EL device described in 10) above, wherein the organic layer using the compound having a benzoxazole ring structure is an electron transport layer.

[0079] 12) In addition, the present invention is the organic EL device described in 10) above, wherein the organic layer using the compound having a benzoxazole ring structure is a hole blocking layer.

[0080] 13) In addition, the present invention is the organic EL device described in 10) above, wherein the organic layer using the compound having a benzoxazole ring structure is a light-emitting layer.

[0081] 14) In addition, the present invention is the organic EL device described in 10) above, wherein the organic layer using the compound having a benzoxazole ring structure is an electron injection layer.

[0082] In the “substituted or unsubstituted aromatic hydrocarbon group”, “substituted or unsubstituted aromatic heterocyclic group” and “substituted or unsubstituted condensed polycyclic aromatic group” represented by R in the general formula (a-1), specifically, phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthrenyl, fluorenyl, spirobifluorenyl, indenyl, pyrenyl, peryl, fluoranthenyl, benzo[9,10]phenanthrenyl, pyridyl, pyrimidine In addition to the above, aryl groups include aryl groups having 6 to 30 carbon atoms and heteroaryl groups having 2 to 20 carbon atoms, such as thiophene, quinolyl, isoquinolyl, benzofuranyl, benzothiophenyl, indolyl, carbazolyl, benzoxazolyl, benzothiazolyl, azafluorenyl, diazafluorenyl, azaspirobifluorenyl, diazaspirobifluorenyl, quinoxalinyl, benzimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothiophenyl, naphthyridinyl, phenanthrolinyl, acridinyl and carbolyl.

[0083] Specific examples of the “substituent” in the “substituted aromatic hydrocarbon group”, “substituted aromatic heterocyclic group” and “substituted condensed polycyclic aromatic group” represented by R in the general formula (a-1) include a deuterium atom, a cyano group and a nitro group; a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom and an iodine atom; a silyl group such as a trimethylsilyl group and a triphenylsilyl group; a linear or branched alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group and a propyl group; a linear or branched alkoxy group having 1 to 6 carbon atoms such as a methoxy group, an ethoxy group and a propoxy group; an alkenyl group such as a vinyl group and an allyl group; an aryloxy group such as a phenoxy group and a tolyloxy group; a benzyloxy group , phenylethoxy and other aryl alkoxy groups; phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthryl, fluorenyl, spirobifluorenyl, indenyl, pyrene, perylenyl, fluoranthenyl, benzo[9,10]phenanthryl and other aromatic hydrocarbon groups or condensed polycyclic aromatic groups; pyridyl, pyrimidinyl, triazine, thienyl, furanyl, pyrrolyl, quinolyl, isoquinolyl, benzofuranyl, benzothienyl, indolyl, carbazolyl, benzoxazolyl, benzothiazolyl, quinoxalinyl, benzimidazolyl, pyrazolyl, dibenzofuranyl, dibenzothienyl, carbazolyl and other aromatic heterocyclic groups, and these substituents may be further substituted by the substituents exemplified above. Furthermore, these substituents and the substituted benzene ring, or a plurality of substituents substituted on the same benzene ring may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, an oxygen atom or a sulfur atom to form a ring.

[0084] In the "carbon atom of a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent", "carbon atom of a cycloalkyl group having 5 to 10 carbon atoms which may have a substituent" or "carbon atom of a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent" represented by R in the general formula (a-1), the "carbon atom of a linear or branched alkyl group having 1 to 6 carbon atoms", "carbon atom of a cycloalkyl group having 5 to 10 carbon atoms" and "carbon atom of a linear or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent" are preferably a carbon atom of a linear or branched alkyl group having 1 to 6 carbon atoms, a carbon atom of a cycloalkyl group having 5 to 10 carbon atoms and a carbon atom of a cycloalkyl group having 2 to 6 carbon atoms The term "branched alkenyl carbon atom" specifically includes methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl, n-hexyl, cyclopentyl, cyclohexyl, 1-adamantyl, 2-adamantyl, vinyl, allyl, isopropenyl, 2-butenyl and the like. These substituents and the substituted benzene ring, or a plurality of substituents substituted on the same benzene ring, may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom or a sulfur atom to form a ring.

[0085] As the "substituent" in the "straight-chain or branched alkyl group having 1 to 6 carbon atoms which may have a substituent", "cycloalkyl group having 5 to 10 carbon atoms which may have a substituent" and "straight-chain or branched alkenyl group having 2 to 6 carbon atoms which may have a substituent" represented by R in the general formula (a-1), the same groups as the groups represented by the "substituent" in the "substituted aromatic hydrocarbon group", "substituted aromatic heterocyclic group" and "substituted condensed polycyclic aromatic group" represented by R in the general formula (a-1) can be listed, and the same forms that can be taken can also be listed.

[0086] As the “carbon atom of a linear or branched alkoxy group having 1 to 6 carbon atoms” and “carbon atom of a cycloalkoxy group having 5 to 10 carbon atoms” in the “carbon atom of a linear or branched alkoxy group having 1 to 6 carbon atoms which may have a substituent” and “carbon atom of a cycloalkoxy group having 5 to 10 carbon atoms which may have a substituent” represented by R in the general formula (a-1), specifically, there can be mentioned a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a tert-butoxy group, an n-pentyloxy group, an n-hexyloxy group, a cyclopentyloxy group, a cyclohexyloxy group, a cycloheptyloxy group, a cyclooctyloxy group, a 1-adamantyloxy group, a 2-adamantyloxy group, and the like. These substituents and the substituted benzene ring, or a plurality of substituents substituted on the same benzene ring, may be bonded to each other via a single bond, a substituted or unsubstituted methylene group, a substituted or unsubstituted amino group, an oxygen atom, or a sulfur atom to form a ring.

[0087] As the "substituent" in the "straight-chain or branched alkoxy group having 1 to 6 carbon atoms which may have a substituent" and the "cycloalkoxy group having 5 to 10 carbon atoms which may have a substituent" represented by R in the general formula (a-1), the same groups as the groups represented by the "substituent" in the "substituted aromatic hydrocarbon group", "substituted aromatic heterocyclic group" and "substituted condensed polycyclic aromatic group" represented by R in the general formula (a-1) can be listed, and the same forms that can be taken can also be listed.

[0088] As the “aromatic hydrocarbon group”, “aromatic heterocyclic group” and “fused polycyclic aromatic group” in the “substituted or unsubstituted aromatic hydrocarbon group”, “substituted or unsubstituted aromatic heterocyclic group” and “substituted or unsubstituted fused polycyclic aromatic group” represented by L1 and L2 in the structural formula (b-1), there can be listed groups obtained by removing one hydrogen atom from the same groups as the “aromatic hydrocarbon group”, “aromatic heterocyclic group” and “fused polycyclic aromatic group” in the “substituted or unsubstituted aromatic hydrocarbon group”, “substituted or unsubstituted aromatic heterocyclic group” and “substituted or unsubstituted fused polycyclic aromatic group” represented by R in the general formula (a-1), and the same forms can be listed as possible forms.

[0089] As the "substituent" in the "substituted aromatic hydrocarbon group", "substituted aromatic heterocyclic group" and "substituted condensed polycyclic aromatic group" represented by L1 and L2 in the structural formula (b-1), the same groups as the groups represented by the "substituent" in the "substituted aromatic hydrocarbon group", "substituted aromatic heterocyclic group" and "substituted condensed polycyclic aromatic group" represented by R in the general formula (a-1) can be listed, and the same forms that can be adopted can also be listed.

[0090] The compound having a benzoxazole ring structure represented by the general formula (a-1) and preferably used in the organic EL element of the present invention can be used as a constituent material of an electron injection layer, an electron transport layer or a hole blocking layer of the organic EL element. In particular, since the mobility of electrons is large, it is a preferred compound as a material for an electron injection layer or an electron transport layer.

[0091] As for the organic EL element of the present invention, since materials for organic EL elements having excellent electron injection and transport properties, thin film stability, and durability are used, compared with existing organic EL elements, the electron transport efficiency from the electron transport layer to the light-emitting layer is improved, the light-emitting efficiency is improved, and the driving voltage is reduced, which can improve the durability of the organic EL element and realize an organic EL element with high efficiency, low driving voltage, and long life.

[0092] The compound having a benzoxazole ring structure of the present invention has the following characteristics: (1) good electron injection characteristics, (2) large electron mobility, (3) excellent hole blocking ability, (4) stable existence in a thin film state, (5) excellent heat resistance, etc. The organic EL element of the present invention has the following characteristics: (6) high luminous efficiency, (7) low luminescence starting voltage, (8) low practical driving voltage, (9) long life, etc.

[0093] As for the compound having a benzoxazole ring structure of the present invention, since the electron injection characteristics are good and the electron mobility is large, the electron transfer efficiency to the light-emitting layer of the organic EL element having an electron injection layer and / or an electron transport layer made by using the compound as an electron injection material and / or an electron transport material is improved, the luminous efficiency is improved, and the driving voltage is reduced, thereby improving the durability of the organic EL element.

[0094] The compound having a benzoxazole ring structure of the present invention has the following characteristics: excellent hole blocking ability and electron transport properties, and is stable in a thin film state, and blocks excitons generated in the light-emitting layer. Therefore, for an organic EL element having a hole blocking layer made using the compound as a hole blocking material, the probability of recombination between holes and electrons is increased, thermal deactivation is suppressed, and thus the luminous efficiency is high, the driving voltage is reduced, and the current resistance is improved, thereby increasing the maximum luminous brightness.

[0095] The compound having a benzoxazole ring structure of the present invention has excellent electron transport properties and a wide band gap. Thus, an organic EL element having a light-emitting layer made of the compound as a main material can form a light-emitting layer by loading a fluorescent light-emitting body, a phosphorescent light-emitting body, or a delayed fluorescent light-emitting body called a dopant, thereby reducing the driving voltage and improving the luminous efficiency.

[0096] Therefore, the compound having a benzoxazole ring structure of the present invention is useful as a material for an electron injection layer, an electron transport layer, a hole blocking layer or a light-emitting layer of an organic EL element, and can improve the luminous efficiency, driving voltage and durability of existing organic EL elements. BRIEF DESCRIPTION OF THE DRAWINGS

[0097] Figure 1 The diagrams show the structures of Compounds 1 to 15 as examples of the compound having a benzoxazole ring structure represented by the general formula (a-1).

[0098] Figure 2 It is a figure which shows the structure of the compound 16-33 which is an example of the compound which has a benzoxazole ring structure represented by general formula (a-1).

[0099] Figure 3 It is a figure which shows the structure of the compound 34-51 which is an example of the compound which has a benzoxazole ring structure represented by general formula (a-1).

[0100] Figure 4 It is a figure which shows the structure of Compounds 52 to 69 which are examples of the compound which has a benzoxazole ring structure represented by General Formula (a-1).

[0101] Figure 5 It is a figure which shows the structure of Compounds 70 to 84 which are examples of the compound which has a benzoxazole ring structure represented by General Formula (a-1).

[0102] Figure 6 It is a figure which shows the structure of Compound 85-96 which are examples of the compound which has a benzoxazole ring structure represented by General Formula (a-1).

[0103] Figure 7 It is a figure which shows the structure of Compounds 97 to 107 which are examples of the compound which has a benzoxazole ring structure represented by General Formula (a-1).

[0104] Figure 8 It is a figure which shows the structure of the compound 108-124 which is an example of the compound which has a benzoxazole ring structure represented by general formula (a-1).

[0105] Fig. 9It is a diagram showing the structures of Compounds 125 to 139 as examples of the compound having a benzoxazole ring structure represented by the general formula (a-1).

[0106] Fig.10 It is a diagram showing the structures of compounds 140 to 154 as examples of the compound having a benzoxazole ring structure represented by the general formula (a-1).

[0107] Fig.11 It is a diagram showing the structures of Compounds 155 to 169 as examples of the compound having a benzoxazole ring structure represented by the general formula (a-1).

[0108] Fig.12 It is a diagram showing the structures of Compounds 170 to 184 as examples of the compound having a benzoxazole ring structure represented by the general formula (a-1).

[0109] Fig.13 It is a diagram showing the structures of compounds 185 to 200 as examples of the compound having a benzoxazole ring structure represented by the general formula (a-1).

[0110] Fig.14 It is a figure which shows the structure of the compound 201-204 which is an example of the compound which has a benzoxazole ring structure represented by general formula (a-1).

[0111] Fig.15 It is a figure which shows the structure of the organic EL element of Examples 58-112 and Comparative Examples 1-2. DETAILED DESCRIPTION

[0112] In the present invention, from the viewpoint of hole blocking ability and electron transporting property, X in the general formula (a-1) is preferably an oxygen atom. That is, the compound having a benzoxazole ring structure represented by the general formula (a-2) is preferred.

[0113] Furthermore, Y is preferably a carbon atom having R, that is, more preferably a compound having a benzoxazole ring structure represented by the above general formula (a-3).

[0114] As for R in the above-mentioned general formula (a-1), from the viewpoint of the stability of the thin film state, it is preferably a hydrogen atom, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aromatic heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, or a group represented by the above-mentioned structural formula (b-1).

[0115] Specifically, the compound having a benzoxazole ring structure represented by the above general formula (a-4) is preferred, and the compound having a benzoxazole ring structure represented by the above general formula (a-5) is more preferred.

[0116] As for L1 and L2 in the above structural formula (b-1), from the viewpoint of hole blocking ability and electron transportability, it is preferably a group selected from substituted or unsubstituted phenylene, substituted or unsubstituted biphenylene, substituted or unsubstituted terphenylene, substituted or unsubstituted naphthylene, and substituted or unsubstituted fluorenylene. In addition, as for L2 in the above structural formula (b-1), it is preferably a substituted or unsubstituted phenylene, or a substituted or unsubstituted biphenylene.

[0117] Among the groups represented by the above structural formula (b-1), preferred groups include groups represented by the following structural formulas.

[0118] [Chemistry 9]

[0119]

[0120] (In the formula, the dotted line represents the bonding site.)

[0121] As for the substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aromatic heterocyclic group and substituted or unsubstituted condensed polycyclic aromatic group represented by R in the above-mentioned general formula (a-1), from the viewpoint of hole blocking ability and electron transporting property, preferably, it is a phenyl group, a naphthyl group, a phenanthrenyl group, a spirobifluorenyl group, a pyridyl group, a substituted or unsubstituted fluorenyl group, or a substituted or unsubstituted triazine group, or a group formed by combining these groups with a phenylene group.

[0122] Among the groups represented by R in the general formula (a-1), preferred groups include groups represented by the following structural formulas.

[0123] [Chemistry 10]

[0124]

[0125] (In the formula, the dotted line represents the bonding site.)

[0126] Among the compounds having a benzoxazole ring structure represented by the above general formula (a-1) which are preferably used in the organic EL device of the present invention, specific examples of preferred compounds are shown below. Figures 1 to 14 In, but not limited to these compounds.

[0127] The compounds having a benzoxazole ring structure of the present invention are novel compounds and can be synthesized, for example, by methods known per se as described below (see, for example, Patent Documents 5 and 6 and Non-Patent Documents 6 and 7).

[0128] [Chemistry 11]

[0129]

[0130] [Chemistry 12]

[0131]

[0132] As for the purification of the compound having a benzoxazole ring structure represented by the general formula (a-1) to (a-7), it can be carried out by purification by column chromatography, adsorption purification by silica gel, activated carbon, activated clay, etc., recrystallization by solvent, crystallization method, sublimation purification method, etc. Identification of the compound can be carried out by NMR analysis. As physical property values, melting point, glass transition temperature (Tg) and work function determination can be listed. The melting point becomes an indicator of vapor deposition, the glass transition temperature (Tg) becomes an indicator of the stability of the thin film state, and the work function becomes an indicator of hole transport and hole blocking properties.

[0133] The melting point and the glass transition temperature (Tg) can be measured, for example, using a powder with a high-sensitivity differential scanning calorimeter (DSC3100SA manufactured by Bruker Eixex).

[0134] The work function can be determined, for example, by forming a 100 nm thin film on an ITO substrate and using an ionization potential measuring apparatus (PYS-202, manufactured by Sumitomo Heavy Industries, Ltd.).

[0135] As the structure of the organic EL element of the present invention, a structure including an anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer and a cathode in sequence on a substrate can be listed, as well as a structure with an electron blocking layer between the hole transport layer and the light-emitting layer, and a structure with a hole blocking layer between the light-emitting layer and the electron transport layer. In these multilayer structures, an organic layer can have the functions of a certain layer or some layers, for example, an organic layer can also be formed as a structure that doubles as a hole injection layer and a hole transport layer, a structure that doubles as an electron injection layer and an electron transport layer, etc. In addition, it can be formed into a structure in which two or more organic layers with the same function are stacked, and it can also be formed into a structure in which two layers of hole transport layers are stacked, a structure in which two layers of light-emitting layers are stacked, and a structure in which two layers of electron transport layers are stacked, etc.

[0136] As the anode of the organic EL element of the present invention, an electrode material having a large work function such as ITO or gold is used.

[0137] As the material of the hole injection layer of the organic EL element of the present invention, porphyrin compounds represented by copper phthalocyanine, starburst-type triphenylamine derivatives, aromatic amine compounds having a structure in which the molecule has two or more triphenylamine structures or carbazole structures, each of which is connected by a single bond or a divalent group not containing a heteroatom, acceptor heterocyclic compounds such as hexacyanoazabenzo[9,10]phenanthrene, and coating-type polymer materials can be used.

[0138] As materials for the hole transport layer of the organic EL element of the present invention, there can be used N,N'-diphenyl-N,N'-di(m-tolyl)benzidine (hereinafter referred to as TPD), N,N'-diphenyl-N,N'-di(α-naphthyl)benzidine (hereinafter referred to as NPD), benzidine derivatives such as N,N,N',N'-tetraphenylbenzidine, 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (hereinafter referred to as TAPC), and aromatic amine compounds having a structure in which the molecule has two or more triphenylamine structures or carbazole structures, each of which is connected by a single bond or a divalent group not containing hetero atoms.

[0139] As materials for the hole injection layer and the hole transport layer, coating-type polymer materials such as poly(3,4-ethylenedioxythiophene) (hereinafter referred to as PEDOT) / poly(styrenesulfonic acid) (hereinafter referred to as PSS) can be used.

[0140] Furthermore, as materials for the hole injection layer and the hole transport layer, products obtained by P-doping tri(bromophenyl)amine antimony hexachloride, axialene derivatives (for example, see Patent Document 7), etc. with the materials commonly used in these layers, and polymer compounds having the structure of benzidine derivatives such as TPD in part of their structure can be used.

[0141] As materials for the electron blocking layer of the organic EL element of the present invention, compounds having an electron blocking effect such as carbazole derivatives such as 4,4',4"-tri(N-carbazyl)triphenylamine (hereinafter referred to as TCTA), 9,9-bis[4-(carbazol-9-yl)phenyl]fluorene, 1,3-bis(carbazol-9-yl)benzene (hereinafter referred to as mCP), 2,2-bis(4-carbazol-9-ylphenyl)adamantane (hereinafter referred to as Ad-Cz), and compounds having a triphenylsilyl and triarylamine structure represented by 9-[4-(carbazol-9-yl)phenyl]-9-[4-(triphenylsilyl)phenyl]-9H-fluorene can be used.

[0142] As the material of the light-emitting layer of the organic EL element of the present invention, in addition to the compound having the benzoxazole ring structure of the present invention, metal complexes of quinolinephenol derivatives headed by Alq3, various metal complexes, anthracene derivatives, bisphenylenebenzene derivatives, pyrene derivatives, oxazole derivatives and polyparaphenylenevinylene derivatives can be used. In addition, the light-emitting layer can be composed of a host material and a dopant material. As the host material, anthracene derivatives are preferably used. In addition to the above-mentioned light-emitting materials headed by the compound having the benzoxazole ring structure of the present invention, heterocyclic compounds having an indole ring as a partial structure of the condensed ring, heterocyclic compounds having a carbazole ring as a partial structure of the condensed ring, carbazole derivatives, thiazole derivatives, benzimidazole derivatives and polydialkylfluorene derivatives can be used. In addition, as the dopant material, quinacridone, coumarin, rubrene, perylene and their derivatives, benzopyran derivatives, rhodamine derivatives and aminostyryl derivatives can be used.

[0143] In addition, phosphorescent light emitters can also be used as materials for the light-emitting layer. As phosphorescent light emitters, phosphorescent light emitters of metal complexes such as iridium and platinum can be used. For example, green phosphorescent light emitters such as Ir(ppy)3, cyan phosphorescent light emitters such as FIrpic and FIr6, and red phosphorescent light emitters such as Btp2Ir(acac) can be listed. As the main material at this time, as the main material for hole injection and transport, in addition to carbazole derivatives such as 4,4'-di(N-carbazolyl)biphenyl (hereinafter referred to as CBP), TCTA and mCP, the compounds having a benzoxazole ring structure of the present invention can also be listed. As the main material for electron transport, para-bis(triphenylsilyl)benzene (hereinafter referred to as UGH2) and 2,2',2"-(1,3,5-phenylene)-tri(1-phenyl-1H-benzimidazole) (hereinafter referred to as TPBI) can be listed. By using such materials, high-performance organic EL elements can be produced.

[0144] In order to avoid concentration quenching, the phosphorescent light-emitting material is preferably doped into the host material by co-evaporation in an amount of 1 to 30% by weight based on the entire light-emitting layer.

[0145] In addition, as the light-emitting material, a material that emits delayed fluorescence, such as PIC-TRZ, CC2TA, PXZ-TRZ, or CDCB derivatives such as 4CzIPN, may be used (see, for example, Non-Patent Document 3).

[0146] As the material of the hole blocking layer of the organic EL element of the present invention, in addition to the compound having a benzoxazole ring structure of the present invention, a compound having a hole blocking effect such as a phenanthroline derivative such as bathocuproine (hereinafter referred to as BCP), a metal complex of a quinolinephenol derivative such as BAlq, various rare earth complexes, oxazole derivatives, triazole derivatives and triazine derivatives can also be used. These materials can also serve as materials for the electron transport layer.

[0147] As materials for the electron transport layer of the organic EL element of the present invention, in addition to the compounds having a benzoxazole ring structure of the present invention, metal complexes of quinolinephenol derivatives headed by Alq3 and BAlq, various metal complexes, triazole derivatives, triazine derivatives, oxadiazole derivatives, pyridine derivatives, benzimidazole derivatives, thiadiazole derivatives, anthracene derivatives, carbodiimide derivatives, quinoxaline derivatives, pyridoindole derivatives, phenanthroline derivatives and silole derivatives can also be used.

[0148] As materials for the electron injection layer of the organic EL element of the present invention, in addition to the compound having a benzoxazole ring structure of the present invention, alkali metal salts such as lithium fluoride and cesium fluoride, alkaline earth metal salts such as magnesium fluoride, metal complexes of quinolinephenol derivatives such as lithium quinolinephenol, metal oxides such as aluminum oxide, and metals such as ytterbium (Yb), samarium (Sm), calcium (Ca), strontium (Sr) and cesium (Cs) can also be used. Depending on the preferred selection of the electron transport layer and the cathode, the electron injection layer can be omitted.

[0149] As the material of the electron injection layer and the electron transport layer, materials generally used in these layers and doped with a metal such as cesium may be used.

[0150] As the cathode of the organic EL element of the present invention, an electrode material having a low work function such as aluminum, or an alloy having an even lower work function such as a magnesium-silver alloy, a magnesium-indium alloy, or an aluminum-magnesium alloy is used as an electrode material.

[0151] These materials used in the respective layers constituting the organic EL element can be formed into thin films by a known method such as a vapor deposition method, a spin coating method, and an ink jet method.

[0152] In addition, these materials can be formed into films individually, or multiple materials can be mixed to form films, and each can be used as a single layer. In addition, a laminated structure between layers formed of these materials individually, a laminated structure between layers formed of mixed films, or a laminated structure between layers formed of these materials individually and layers formed of multiple materials mixed to form films can also be made.

[0153] Example

[0154] Hereinafter, the embodiments of the present invention will be specifically described by way of examples. However, the present invention is not limited to the following examples unless the scope of the invention exceeds the scope of the invention.

[0155] (Example 1)

[0156] <Synthesis of 4,6-bis(4-naphthyl-1-yl-phenyl)-2-(4'-cyano-biphenyl-4-yl)-benzoxazole (Compound-2)>

[0157] 2-(4-chlorophenyl)-4,6-bis(4-naphthyl-1-yl-phenyl)-benzoxazole: 8.8 g, 4-cyanophenylboronic acid: 3.2 g, tris(dibenzylideneacetone)dipalladium(0): 0.3 g, tricyclohexylphosphine: 0.4 g, tripotassium phosphate: 5.4 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by crystallization using a mixed solvent of monochlorobenzene / acetone to obtain 4,6-bis(4-naphthyl-1-yl-phenyl)-2-(4'-cyano-biphenyl-4-yl)-benzoxazole (Compound-2) as a light yellow powder: 7.2 g (yield: 83%).

[0158] [Chemistry 13]

[0159]

[0160] The structure of the obtained light yellow powder was identified using NMR.

[0161] use 1 The following 32 hydrogen signals were detected by H-NMR (CDCl3).

[0162] δ(ppm)=8.52(2H), 8.33(2H), 8.13(1H), 8.05(1H), 8.04(1H), 8.01-7.88(7H), 7.85-7.78(6H), 7.75(2H), 7.70(2H), 7.65-7.47(8H)

[0163] (Example 2)

[0164] <Synthesis of 4,6-bis(phenanthrene-9-yl)-2-(4'-cyano-biphenyl-4-yl)-benzoxazole (Compound-10)>

[0165] 2-(4-chloro-phenyl)-4,6-bis(phenanthrene-9-yl)-benzoxazole: 10.0 g, 4-cyanophenylboronic acid: 3.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.5 g, tricyclohexylphosphine: 0.5 g, tripotassium phosphate: 7.3 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a monochlorobenzene solvent to obtain 4,6-bis(phenanthrene-9-yl)-2-(4'-cyano-biphenyl-4-yl)-benzoxazole (Compound-10) as a white powder: 4.0 g (yield: 36%).

[0166] [Chemistry 14]

[0167]

[0168] The structure of the obtained white powder was identified using NMR.

[0169] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0170] δ(ppm)=8.85(2H), 8.79(2H), 8.35(2H), 8.17(1H), 8.05(1H), 8.04(1H), 7.98(2H), 7.91(2H), 7.80-7.58(12H), 7.65(2H), 7.59(1H)

[0171] (Example 3)

[0172] <Synthesis of 2-(4"-cyano-[1,1'; 4',1"]terphenyl-4-yl)-4,6-di(naphthalen-1-yl)-benzoxazole (Compound-22)>

[0173] 4,6-bis(naphthalene-1-yl)-2-(4-chloro-phenyl)-benzoxazole: 8.0 g, 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile: 6.1 g, tris(dibenzylideneacetone)dipalladium(0): 0.8 g, tricyclohexylphosphine: 0.9 g, tripotassium phosphate: 10.6 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, water was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The crude product was purified by recrystallization using monochlorobenzene solvent to obtain 9.3 g (yield: 90%) of white powder of 4,6-bis(naphthalen-1-yl)-2-(4"-cyano-[1,1';4',1"]terphenyl-4-yl)-benzoxazole (Compound-22).

[0174] [Chemistry 15]

[0175]

[0176] The structure of the obtained white powder was identified using NMR.

[0177] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0178] δ(ppm)=8.36(2H), 8.14(1H), 8.03(1H), 7.98(3H), 7.94(1H), 7.85(1H), 7.84-7.69(11H), 7.68(2H), 7.61(2H), 7.54(3H), 7.48(1H)

[0179] (Example 4)

[0180] <Synthesis of 4,6-bis(biphenyl-4-yl)-2-(4"-cyano-[1,1';4',1"]terphenyl-4-yl)-benzoxazole (Compound-23)>

[0181] 4,6-bis(biphenyl-4-yl)-2-(4-chloro-phenyl)-benzoxazole: 11.4 g, 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile: 7.8 g, tris(dibenzylideneacetone)dipalladium(0): 1.0 g, tricyclohexylphosphine: 1.2 g, tripotassium phosphate: 13.6 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol and water were added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The crude product was purified by recrystallization using 1,2-dichlorobenzene solvent to obtain 13.7 g (yield: 95%) of yellow powder of 4,6-bis(biphenyl-4-yl)-2-(4"-cyano-[1,1';4',1"]terphenyl-4-yl)-benzoxazole (Compound-23).

[0182] [Chemistry 16]

[0183]

[0184] The structure of the obtained yellow powder was identified using NMR.

[0185] use 1 The following 32 hydrogen signals were detected by H-NMR (CDCl3).

[0186] δ(ppm)=8.45(2H), 8.26(2H), 7.92(1H), 7.90-7.67(21H), 7.52(4H), 7.42(2H)

[0187] (Example 5)

[0188] <Synthesis of 4,6-bis(4-naphthyl-1-yl-phenyl)-2-(4"-cyano-[1,1',4',1"]terphenyl-4-yl)-benzoxazole (Compound-24)>

[0189] 8.0 g of 2-(4-chlorophenyl)-4,6-bis(4-naphthalen-1-yl-phenyl)-benzoxazole, 4.6 g of 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile, 0.3 g of tris(dibenzylideneacetone)dipalladium(0), 0.4 g of tricyclohexylphosphine, and 5.4 g of tripotassium phosphate were placed in a reaction container, and the mixture was stirred under reflux overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the mixture was dispersed, washed, and filtered to obtain a crude product. The crude product was purified by recrystallization using monochlorobenzene to obtain 3.2 g (yield: 32%) of light yellow powder of 4,6-bis(4-naphthyl-1-yl-phenyl)-2-(4"-cyano-[1,1',4',1"]terphenyl-4-yl)-benzoxazole (Compound-24).

[0190] [Chemistry 17]

[0191]

[0192] The structure of the obtained light yellow powder was identified using NMR.

[0193] use 1 The following 36 hydrogen signals were detected by H-NMR (CDCl3).

[0194] δ(ppm)=8.50(2H), 8.34(2H), 8.13(1H), 8.06(2H), 8.02-7.91(7H), 7.89(2H), 7.84(4H), 7.81-7.72(6H), 7.70(2H), 7.65-7.47(8H)

[0195] (Example 6)

[0196] <Synthesis of 2-[4-{4-(4'-cyano-biphenyl-4-yl)-naphthalen-1-yl}-phenyl]-4,6-diphenyl-benzoxazole (Compound-27)>

[0197] A reaction vessel was charged with 6.8 g of 2-(4-chloro-phenyl)-4,6-diphenyl-benzoxazole, 8.1 g of 4'-{4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-naphthalen-1-yl}-biphenyl-4-carbonitrile, 0.5 g of tris(dibenzylideneacetone)dipalladium(0), 0.5 g of tricyclohexylphosphine, and 7.6 g of tripotassium phosphate, and the mixture was stirred under reflux overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, dichloromethane / water was added to the system, and the organic layer taken out by extraction and separation was concentrated. The obtained concentrate was purified by column chromatography (carrier: silica gel, eluent: dichloromethane / n-heptane) to obtain 7.3 g (yield: 63%) of light yellow powder of 2-[4-{4-(4'-cyano-biphenyl-4-yl)-naphthalen-1-yl}-phenyl]-4,6-diphenyl-benzoxazole (Compound-27).

[0198] [Chemistry 18]

[0199]

[0200] The structure of the obtained light yellow powder was identified using NMR.

[0201] use 1 The following 30 hydrogen signals were detected by H-NMR (CDCl3).

[0202] δ(ppm)=8.50(2H), 8.17(2H), 8.06(2H), 7.88-7.66(14H), 7.64-7.41(10H)

[0203] (Example 7)

[0204] <Synthesis of 2-(4'-cyano-biphenyl-4-yl)-6-{4-(4,6-diphenyl-[1,3,5]triazine-2-yl)-phenyl}-4-phenyl-benzoxazole (Compound-75)>

[0205] 2-(4-chlorophenyl)-6-{4-(4,6-diphenyl-[1,3,5]triazine-2-yl)-phenyl}-4-phenyl-benzoxazole: 10.0 g, 4-cyanophenylboronic acid: 2.6 g, tris(dibenzylideneacetone)dipalladium(0): 0.8 g, tricyclohexylphosphine: 0.9 g, tripotassium phosphate: 10.4 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, H2O was added, and the mixture was dispersed, washed, and filtered to obtain a crude product. The crude product was purified by column chromatography (carrier: silica gel, eluent: dichloromethane / ethyl acetate) to obtain 7.0 g (yield: 63%) of light yellow powder of 2-(4'-cyano-biphenyl-4-yl)-6-{4-(4,6-diphenyl-[1,3,5]triazine-2-yl)-phenyl}-4-phenyl-benzoxazole (Compound-75).

[0206] [Chemistry 19]

[0207]

[0208] The structure of the obtained light yellow powder was identified using NMR.

[0209] use 1 The following 29 hydrogen signals were detected by H-NMR (CDCl3).

[0210] δ(ppm)=8.91(2H), 8.83(4H), 8.45(2H), 8.17(2H), 7.93(2H), 7.91(2H), 7.79(4H), 7.77(2H), 7.70-7.57(8H), 7.51(1H)

[0211] (Example 8)

[0212] <Synthesis of 2-(4'-cyano-[1,1'; 4',1"]terphenyl-4-yl)-4-phenyl-6-{4-(pyridin-3-yl)-phenyl}-benzoxazole (Compound-77)>

[0213] A reaction vessel was charged with 2-(4-chloro-phenyl)-4-phenyl-6-{4-(pyridin-3-yl)-phenyl}-benzoxazole: 10.6 g, 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile: 7.4 g, tris(dibenzylideneacetone)dipalladium(0): 0.6 g, tricyclohexylphosphine: 0.4 g, and tripotassium phosphate: 9.8 g, and the mixture was stirred under reflux overnight in a mixed solvent of 1,4-dioxane and H2O. After cooling naturally, ethyl acetate / water was added to the system, and the organic layer taken out by extraction and separation operation was concentrated. The obtained concentrate was purified by column chromatography (carrier: silica gel, eluent: dichloromethane / ethyl acetate) to obtain 2-(4'-cyano-[1,1';4',1"]triphenyl-4-yl)-4-phenyl-6-{4-(pyridin-3-yl)-phenyl}-benzoxazole (Compound-77) as a light yellow powder: 2.1 g (yield: 15%).

[0214] [Chemistry 20]

[0215]

[0216] The structure of the obtained light yellow powder was identified using NMR.

[0217] use 1 The following 27 hydrogen signals were detected by H-NMR (CDCl3).

[0218] δ(ppm)=8.97(1H), 8.66(1H), 8.44(2H), 8.16(2H), 7.98(1H), 7.90-7.71(16H), 7.61(2H), 7.49(1H), 7.44(1H)

[0219] (Example 9)

[0220] <Synthesis of 2-(4'-cyano-biphenyl-4-yl)-6-{4-(4,6-diphenyl-[1,3,5]triazine-2-yl)-phenyl}-benzoxazole (Compound-84)>

[0221] 2-(4-chloro-phenyl)-6-{4-(4,6-diphenyl-[1,3,5]triazine-2-yl)-phenyl}-benzoxazole: 15.0 g, 4-cyanophenylboronic acid: 4.5 g, tris(dibenzylideneacetone)dipalladium(0): 1.3 g, tricyclohexylphosphine: 1.6 g, tripotassium phosphate: 17.8 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol and water were added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using 1,2-dichlorobenzene solvent to obtain 5.3 g (yield: 31%) of yellow powder of 2-(4'-cyano-biphenyl-4-yl)-6-{4-(4,6-diphenyl-[1,3,5]triazine-2-yl)-phenyl}-benzoxazole (Compound-84).

[0222] [Chemistry 21]

[0223]

[0224] The structure of the obtained yellow powder was identified using NMR.

[0225] use 1 The following 25 hydrogen signals were detected by H-NMR (CDCl3).

[0226] δ(ppm)=8.93(2H), 8.84(4H), 8.44(2H), 7.97(1H), 7.92(3H), 7.85-7.75(7H), 7.68-7.59(6H)

[0227] (Example 10)

[0228] <Synthesis of 4-(biphenyl-4-yl)-6-(4'-cyano-biphenyl-4-yl)-2-([1,1';4',1"]terphenyl-4-yl)-benzoxazole (Compound-104)>

[0229] A reaction vessel was charged with 6-chloro-4-(biphenyl-4-yl)-6-([1,1'; 4',1"]terphenyl-4-yl)-benzoxazole: 6.0 g, 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile: 4.1 g, tris(dibenzylideneacetone)dipalladium(0): 0.3 g, tricyclohexylphosphine: 0.3 g, and tripotassium phosphate: 4.8 g. The mixture was stirred in 1,4-dioxane, H2O. Reflux with stirring under mixed solvent overnight. After natural cooling, add water to the system for dispersion, washing and filtration to obtain a crude product. The obtained crude product is purified by crystallization using a monochlorobenzene / acetone mixed solvent to obtain 4-(biphenyl-4-yl)-6-(4'-cyano-biphenyl-4-yl)-2-([1,1';4',1"]triphenyl-4-yl)-benzoxazole (Compound-104) as a light yellow powder: 2.1 g (yield: 28%).

[0230] [Chemistry 22]

[0231]

[0232] The structure of the obtained light yellow powder was identified using NMR.

[0233] use 1 The following 32 hydrogen signals were detected by H-NMR (CDCl3).

[0234] δ(ppm)=8.44(2H), 8.26(2H), 7.91-7.66(22H), 7.52(4H), 7.42(2H)

[0235] (Example 11)

[0236] <Synthesis of 4,6-bis(4'-cyano-biphenyl-4-yl)-2-(biphenyl-4-yl)-benzoxazole (Compound-105)>

[0237] 4-Bromo-6-chloro-2-(biphenyl-4-yl)-benzoxazole: 6.0 g, 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile: 8.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.7 g, tricyclohexylphosphine: 0.7 g, tripotassium phosphate: 10.6 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a monochlorobenzene solvent to obtain 4.5 g (yield: 58%) of a light yellow powder of 4,6-bis(4'-cyano-biphenyl-4-yl)-2-(biphenyl-4-yl)-benzoxazole (Compound-105).

[0238] [Chemistry 23]

[0239]

[0240] The structure of the obtained light yellow powder was identified using NMR.

[0241] use 1 The following 27 hydrogen signals were detected by H-NMR (CDCl3).

[0242] δ(ppm)=8.41(2H), 8.29(2H), 7.90-7.67(20H), 7.52(2H), 7.45(1H)

[0243] (Example 12)

[0244] <Synthesis of 6-(4'-cyano-biphenyl-4-yl)-2-(4'-cyano-[1,1';4',1"]terphenyl-4-yl)-4-phenyl-benzoxazole (Compound-106)>

[0245] A reaction vessel was charged with 6-chloro-2-(4-chloro-phenyl)-4-phenyl-benzoxazole: 14.0 g, 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile: 23.3 g, tris(dibenzylideneacetone)dipalladium(0): 2.0 g, tricyclohexylphosphine: 2.0 g, and tripotassium phosphate: 23.2 g, and the mixture was refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, ethyl acetate / water was added to the system, and the organic layer taken out by extraction and separation operation was concentrated. The obtained concentrate was purified by column chromatography (carrier: silica gel, eluent: dichloromethane / ethyl acetate) to obtain 4.6 g (yield: 20%) of light yellow powder of 6-(4'-cyano-biphenyl-4-yl)-2-(4'-cyano-[1,1';4',1"]triphenyl-4-yl)-4-phenyl-benzoxazole (Compound-106).

[0246] [Chemistry 24]

[0247]

[0248] The structure of the obtained light yellow powder was identified using NMR.

[0249] use 1 The following 27 hydrogen signals were detected by H-NMR (CDCl3).

[0250] δ(ppm)=8.46(2H), 8.15(2H), 7.90-7.72(20H), 7.61(2H), 7.50(1H)

[0251] (Example 13)

[0252] <Synthesis of 4,6-bis(biphenyl-4-yl)-2-(4'-cyano-biphenyl-3-yl)-benzoxazole (Compound-108)>

[0253] 4,6-bis(biphenyl-4-yl)-2-(3-chloro-phenyl)-benzoxazole: 10.5 g, 4-cyanophenylboronic acid: 3.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.5 g, tricyclohexylphosphine: 0.6 g, tripotassium phosphate: 8.3 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a monochlorobenzene solvent to obtain 4,6-bis(biphenyl-4-yl)-2-(4'-cyano-biphenyl-3-yl)-benzoxazole (Compound-108) as a white powder: 9.6 g (yield: 81%).

[0254] [Chemistry 25]

[0255]

[0256] The structure of the obtained white powder was identified using NMR.

[0257] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0258] δ(ppm)=8.57(1H), 8.41(1H), 8.23(2H), 7.92(1H), 7.88-7.65(17H), 7.52(4H), 7.42(2H)

[0259] (Example 14)

[0260] <Synthesis of 4,6-bis(biphenyl-4-yl)-2-(3'-cyano-biphenyl-3-yl)-benzoxazole (Compound-109)>

[0261] 4,6-bis(biphenyl-4-yl)-2-(3-chloro-phenyl)-benzoxazole: 9.6 g, 3-cyanophenylboronic acid: 5.3 g, tris(dibenzylideneacetone)dipalladium(0): 0.5 g, tricyclohexylphosphine: 0.5 g, tripotassium phosphate: 7.6 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a monochlorobenzene solvent to obtain 4,6-bis(biphenyl-4-yl)-2-(3'-cyano-biphenyl-3-yl)-benzoxazole (Compound-109) as a white powder: 2.6 g (yield: 24%).

[0262] [Chemistry 26]

[0263]

[0264] The structure of the obtained white powder was identified using NMR.

[0265] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0266] δ(ppm)=8.55(1H), 8.41(1H), 8.24(2H), 8.02(1H), 7.96(1H), 7.92(1H), 7.88(1H), 7.86-7.60(14H), 7.52(4H), 7.42(2H)

[0267] (Example 15)

[0268] <Synthesis of 4,6-bis(4-naphthyl-1-yl-phenyl)-2-(3'-cyano-biphenyl-4-yl)-benzoxazole (Compound-110)>

[0269] 4,6-bis(4-naphth-1-yl-phenyl)-2-(4-chloro-phenyl)-benzoxazole: 7.0 g, 3-cyanophenylboronic acid: 1.8 g, tris(dibenzylideneacetone)dipalladium(0): 0.3 g, tricyclohexylphosphine: 0.3 g, tripotassium phosphate: 7.0 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, toluene / water was added to the system, and the organic layer taken out by extraction and separation operation was concentrated. The obtained concentrate was purified by column chromatography (carrier: silica gel, eluent: toluene / n-heptane) to obtain 4,6-bis(4-naphth-1-yl-phenyl)-2-(3'-cyano-biphenyl-4-yl)-benzoxazole (Compound-110) as a light yellow powder: 5.5 g (yield: 71%).

[0270] [Chemistry 27]

[0271]

[0272] The structure of the obtained light yellow powder was identified using NMR.

[0273] use 1 The following 32 hydrogen signals were detected by H-NMR (CDCl3).

[0274] δ(ppm)=8.51(2H), 8.33(2H), 8.13(1H), 8.06(1H), 8.04(1H), 8.01-7.84(9H), 7.77(3H), 7.71(3H), 7.66-7.41(10H)

[0275] (Example 16)

[0276] <Synthesis of 4,6-bis(4-naphth-1-yl-phenyl)-2-(3'-cyano-biphenyl-3-yl)-benzoxazole (Compound-111)>

[0277] 4,6-bis(4-naphthyl-1-yl-phenyl)-2-(3-chloro-phenyl)-benzoxazole: 12.0 g, 3-cyanophenylboric acid: 3.3 g, tris(dibenzylideneacetone)dipalladium(0): 0.5 g, tricyclohexylphosphine: 0.5 g, tripotassium phosphate: 8.0 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using toluene solvent to obtain 4,6-bis(4-naphthyl-1-yl-phenyl)-2-(3'-cyano-biphenyl-3-yl)-benzoxazole (Compound-111) as a white powder: 10.0 g (yield: 76%).

[0278] [Chemistry 28]

[0279]

[0280] The structure of the obtained white powder was identified using NMR.

[0281] use 1 The following 32 hydrogen signals were detected by H-NMR (CDCl3).

[0282] δ(ppm)=8.58(1H), 8.45(1H), 8.32(2H), 8.13(1H), 8.05(1H), 8.04(2H), 7 .98(3H), 7.95(2H), 7.91(3H), 7.81-7.65(8H), 7.62(2H), 7.59-7.48(6H)

[0283] (Example 17)

[0284] <Synthesis of 4,6-bis(phenanthrene-9-yl)-2-(3'-cyano-biphenyl-4-yl)-benzoxazole (Compound-115)>

[0285] 2-(4-chloro-phenyl)-4,6-bis(phenanthrene-9-yl)-benzoxazole: 10.0 g, 3-cyanophenylboronic acid: 3.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.5 g, tricyclohexylphosphine: 0.5 g, tripotassium phosphate: 7.3 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using toluene solvent to obtain 4,6-bis(phenanthrene-9-yl)-2-(3'-cyano-biphenyl-4-yl)-benzoxazole (Compound-115) as a white powder: 8.4 g (yield: 75%).

[0286] [Chemistry 29]

[0287]

[0288] The structure of the obtained white powder was identified using NMR.

[0289] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0290] δ(ppm)=8.84(2H), 8.79(2H), 8.35(2H), 8.18(1H), 8.06(1H), 8.05(1H), 7.9 8(2H), 7.92(3H), 7.86(1H), 7.78(1H), 7.77-7.65(9H), 7.62(2H), 7.58(1H)

[0291] (Example 18)

[0292] <Synthesis of 2-(3'-cyano-biphenyl-3-yl)-6-(9,9'-spirobi[9H]fluoren-2-yl)-benzoxazole (Compound-117)>

[0293] 2-(3-chloro-phenyl)-6-(9,9'-spirobi[9H]fluoren-2-yl)-benzoxazole: 10.5 g, 3-cyanophenylboronic acid: 3.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.5 g, tricyclohexylphosphine: 0.5 g, tripotassium phosphate: 8.2 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, ethyl acetate / water was added to the system, and the organic layer taken out by extraction and separation operation was concentrated. The obtained concentrate was purified by column chromatography (carrier: silica gel, eluent: dichloromethane / n-heptane) to obtain 5.0 g (yield: 48%) of light yellow powder of 2-(3'-cyano-biphenyl-3-yl)-6-(9,9'-spirobi[9H]fluorene-2-yl)-benzoxazole (Compound-117).

[0294] [Chemistry 30]

[0295]

[0296] The structure of the obtained light yellow powder was identified using NMR.

[0297] use 1 The following 26 hydrogen signals were detected by H-NMR (CDCl3).

[0298] δ(ppm)=8.45(1H), 8.27(1H), 7.98(1H), 7.97(1H), 7.91(4H), 7.72(4H), 7.69(1H), 7.64(1H), 7.60(1H), 7.49(1H), 7.42(3H), 7.16(3H), 7.03(1H), 6.83(2H), 6.78(1H)

[0299] (Example 19)

[0300] <Synthesis of 6-(9,9-diphenyl-9H-fluoren-3-yl)-2-(3'-cyano-biphenyl-3-yl)-benzoxazole (Compound-118)>

[0301] 2-(3-chloro-phenyl)-6-(9,9-diphenyl-9H-fluoren-3-yl)-benzoxazole: 10.5 g, 3-cyanophenylboronic acid: 3.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.5 g, tricyclohexylphosphine: 0.5 g, tripotassium phosphate: 8.2 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a monochlorobenzene solvent to obtain 6-(9,9-diphenyl-9H-fluoren-3-yl)-2-(3'-cyano-biphenyl-3-yl)-benzoxazole (Compound-118) as a white powder: 6.4 g (yield: 54%).

[0302] [Chemistry 31]

[0303]

[0304] The structure of the obtained white powder was identified using NMR.

[0305] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0306] δ(ppm)=8.53(1H), 8.35(1H), 8.03(2H), 7.97(1H), 7.90(2H), 7.88(1H) ,7.76(2H),7.72(2H),7.65(1H),7.56(2H),7.45(2H),7.38-7.22(11H)

[0307] (Example 20)

[0308] <Synthesis of 6-(9,9-diphenyl-9H-fluoren-4-yl)-2-(3'-cyano-biphenyl-3-yl)-benzoxazole (Compound-119)>

[0309] 2-(3-chloro-phenyl)-6-(9,9-diphenyl-9H-fluoren-4-yl)-benzoxazole: 10.5 g, 3-cyanophenylboronic acid: 3.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.5 g, tricyclohexylphosphine: 0.5 g, tripotassium phosphate: 8.2 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by crystallization using a mixed solvent of toluene / acetone to obtain 6-(9,9-diphenyl-9H-fluoren-4-yl)-2-(3'-cyano-biphenyl-3-yl)-benzoxazole (Compound-119) as a white powder: 6.4 g (yield: 54%).

[0310] [Chemistry 32]

[0311]

[0312] The structure of the obtained white powder was identified using NMR.

[0313] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0314] δ(ppm)=8.55(1H), 8.38(1H), 8.03(1H), 7.98(1H), 7.94(1H), 7.79(2H), 7.74(1H), 7.72(1H), 7.6 5(1H), 7.58(1H), 7.50(1H), 7.42(1H), 7.35(2H), 7.32-7.23(10H), 7.20(1H), 7.03(1H), 6.92(1H)

[0315] (Example 21)

[0316] <Synthesis of 2-(4"-cyano-[1,1'; 4',1"]terphenyl-4-yl)-4,6-diphenyl-benzoxazole (Compound-120)>

[0317] 2-(4-chloro-phenyl)-4,6-diphenyl-benzoxazole: 8.8 g, 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile: 8.4 g, tris(dibenzylideneacetone)dipalladium(0): 1.1 g, tricyclohexylphosphine: 1.3 g, tripotassium phosphate: 14.7 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, water was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The crude product was purified by recrystallization using monochlorobenzene as a solvent to obtain 11.5 g (yield: 95%) of light yellow powder of 2-(4"-cyano-[1,1';4',1"]terphenyl-4-yl)-4,6-diphenyl-benzoxazole (Compound-120).

[0318] [Chemistry 33]

[0319]

[0320] The structure of the obtained light yellow powder was identified using NMR.

[0321] use 1 The following 24 hydrogen signals were detected by H-NMR (CDCl3).

[0322] δ(ppm)=8.41(2H), 8.16(2H), 7.89-7.67(14H), 7.65-7.38(6H)

[0323] (Example 22)

[0324] <Synthesis of 2-(4"-cyano-[1,1'; 4',1"]terphenyl-4-yl)-6-(9,9'-spirobi[9H]fluoren-4-yl)-benzoxazole (Compound-123)>

[0325] 2-(4-chloro-phenyl)-6-(9,9'-spirobi[9H]fluorene-4-yl)-benzoxazole: 6.5 g, 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile: 4.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.3 g, tricyclohexylphosphine: 0.3 g, tripotassium phosphate: 7.6 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, water was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The crude product was purified by crystallization using a chlorobenzene / acetone mixed solvent to obtain 7.5 g (yield: 91%) of light yellow powder of 2-(4"-cyano-[1,1';4',1"]terphenyl-4-yl)-6-(9,9'-spirobi[9H]fluorene-4-yl)-benzoxazole (Compound-123).

[0326] [Chemistry 34]

[0327]

[0328] The structure of the obtained light yellow powder was identified using NMR.

[0329] use 1 The following 30 hydrogen signals were detected by H-NMR (CDCl3).

[0330] δ(ppm)=8.46(2H), 8.00(1H), 7.90(2H), 7.89(2H), 7.85(3H), 7.80(4H), 7.76(2H), 7.68(1H), 7.42(2H), 7.30(1H), 7.19(3H), 7.05(3H), 6.86(2H), 6.79(1H), 6.74(1H)

[0331] (Example 23)

[0332] <Synthesis of 2-(4"-cyano-[1,1'; 4',1"]terphenyl-3-yl)-4,6-diphenyl-benzoxazole (Compound-127)>

[0333] 2-(3-chloro-phenyl)-4,6-diphenyl-benzoxazole: 7.1 g, 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile: 6.2 g, tris(dibenzylideneacetone)dipalladium(0): 0.5 g, tricyclohexylphosphine: 0.5 g, tripotassium phosphate: 7.9 g were placed in a reaction container, and stirred under reflux overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The crude product was purified by recrystallization using 1,2-dichlorobenzene as a solvent to obtain 5.3 g (yield: 54%) of white powder of 2-(4″-cyano-[1,1′;4′,1″]terphenyl-3-yl)-4,6-diphenyl-benzoxazole (Compound-127).

[0334] [Chemistry 35]

[0335]

[0336] The structure of the obtained white powder was identified using NMR.

[0337] use 1 The following 24 hydrogen signals were detected by H-NMR (CDCl3).

[0338] δ(ppm)=8.60(1H), 8.36(1H), 8.14(2H), 7.89-7.71(13H), 7.67(1H), 7.63-7.40(6H)

[0339] (Example 24)

[0340] <Synthesis of 4,6-bis(biphenyl-4-yl)-2-(4"-cyano-[1,1';4',1"]terphenyl-3-yl)-benzoxazole (Compound-128)>

[0341] 4,6-bis(biphenyl-4-yl)-2-(3-chloro-phenyl)-benzoxazole: 8.0 g, 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile: 4.8 g, tris(dibenzylideneacetone)dipalladium(0): 0.4 g, tricyclohexylphosphine: 0.4 g, tripotassium phosphate: 6.4 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and dispersion washing and filtration were performed to obtain a crude product. The crude product was purified by recrystallization using 1,2-dichlorobenzene solvent to obtain 7.2 g (yield: 71%) of white powder of 4,6-bis(biphenyl-4-yl)-2-(4"-cyano-[1,1';4',1"]terphenyl-3-yl)-benzoxazole (Compound-128).

[0342] [Chemistry 36]

[0343]

[0344] The structure of the obtained white powder was identified using NMR.

[0345] use 1 The following 32 hydrogen signals were detected by H-NMR (CDCl3).

[0346] δ(ppm)=8.64(1H), 8.38(1H), 8.25(2H), 7.92(1H), 7.89-7.81(8H), 7.81-7.64(13H), 7.52(4H), 7.42(2H)

[0347] (Example 25)

[0348] <Synthesis of 2-(4"-cyano-[1,1'; 4',1"]terphenyl-3-yl)-4,6-di(naphthalen-1-yl)-benzoxazole (Compound-130)>

[0349] 2-(3-chloro-phenyl)-4,6-di(naphthalene-1-yl)-benzoxazole: 9.1 g, 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile: 6.1 g, tris(dibenzylideneacetone)dipalladium(0): 0.5 g, tricyclohexylphosphine: 0.5 g, tripotassium phosphate: 8.0 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The crude product was purified by recrystallization using monochlorobenzene solvent to obtain 1.8 g (yield: 15%) of white powder of 2-(4"-cyano-[1,1';4',1"]terphenyl-3-yl)-4,6-di(naphthalen-1-yl)-benzoxazole (Compound-130).

[0350] [Chemistry 37]

[0351]

[0352] The structure of the obtained white powder was identified using NMR.

[0353] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0354] δ(ppm)=8.53(1H), 8.28(1H), 8.15(1H), 8.03(1H), 7.97(3H), 7.94(1H), 7.86(1H), 7.84-7.73(8H), 7.68(4H), 7.65-7.42(7H)

[0355] (Example 26)

[0356] <Synthesis of 2-(4"'-cyano-[1,1'; 4',1"; 4",1"']quaterphenyl-4-yl)-6-(phenanthrene-9-yl)-benzoxazole (Compound-136)>

[0357] A reaction vessel was charged with 2-(4-chloro-phenyl)-6-(phenanthrene-9-yl)-benzoxazole: 10.0 g, 4-(4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-[1,1';4',1"]terphenyl-4"-carbonitrile: 11.3 g, tris(dibenzylideneacetone)dipalladium(0): 0.7 g, tricyclohexylphosphine: 0.7 g, and tripotassium phosphate: 10.5 g. In 1,4-dioxane, Reflux with stirring under H2O mixed solvent for one night. After natural cooling, methanol is added into the system for dispersion, washing and filtration to obtain a crude product. The obtained crude product is purified by recrystallization using 1,2-dichlorobenzene solvent to obtain 6-(phenanthrene-9-yl)-2-(4"'-cyano-[1,1';4',1";4",1"']tetraphenyl-4-yl)-benzoxazole (Compound-136) as a yellow powder: 13.1 g (yield: 85%).

[0358] [Chemistry 38]

[0359]

[0360] The structure of the obtained yellow powder was identified using NMR.

[0361] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0362] δ(ppm)=8.84(1H), 8.79(1H), 8.44(2H), 7.97(2H), 7.94(1H), 7.88(2H), 7.86-7.77(12H), 7.75(3H), 7.67(2H), 7.60(2H)

[0363] (Example 27)

[0364] <Synthesis of 2-(4"'-cyano-[1,1'; 4',1"; 4",1"']quaterphenyl-4-yl)-6-(phenanthrene-9-yl)-4-phenyl-benzoxazole (Compound-137)>

[0365] A reaction vessel was charged with 2-(4-chloro-phenyl)-6-(phenanthrene-9-yl)-4-phenyl-benzoxazole: 10.0 g, 4-(4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-[1,1';4',1"]terphenyl-4"-carbonitrile: 9.5 g, tris(dibenzylideneacetone)dipalladium(0): 0.6 g, tricyclohexylphosphine: 0.6 g, and tripotassium phosphate: 8.8 g. The mixture was stirred in 1,4-dioxane. , H2O mixed solvent, reflux with stirring overnight. After natural cooling, methanol is added into the system for dispersion, washing and filtration to obtain a crude product. The obtained crude product is purified by recrystallization using monochlorobenzene solvent to obtain 2-(4"'-cyano-[1,1';4',1";4",1"']tetraphenyl-4-yl)-6-(phenanthrene-9-yl)-4-phenyl-benzoxazole (Compound-137) as a yellow powder: 11.9 g (yield: 82%).

[0366] [Chemistry 39]

[0367]

[0368] The structure of the obtained yellow powder was identified using NMR.

[0369] use 1 The following 32 hydrogen signals were detected by H-NMR (CDCl3).

[0370] δ(ppm)=8.85(1H), 8.80(1H), 8.48(2H), 8.19(2H), 8.07(1H), 7.96(1H), 7.86( 4H), 7.81(6H), 7.78(5H), 7.73(4H), 7.69(1H), 7.63(1H), 7.58(2H), 7.46(1H)

[0371] (Example 28)

[0372] <Synthesis of 2-[4-{4-(4'-cyano-biphenyl-4-yl)-naphthalen-1-yl}-phenyl]-6-(phenanthrene-9-yl)-benzoxazole (Compound-138)>

[0373] 8.0 g of 2-(4-chloro-phenyl)-6-(phenanthrene-9-yl)-benzoxazole, 10.2 g of 4'-{4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-naphthalene-1-yl}-biphenyl-4-carbonitrile, 0.5 g of tris(dibenzylideneacetone)dipalladium(0), 0.6 g of tricyclohexylphosphine, and 12.6 g of tripotassium phosphate were placed in a reaction container, and the mixture was stirred under reflux overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the mixture was dispersed, washed, and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using monochlorobenzene as a solvent to obtain 11.3 g (yield: 85%) of yellow powder of 2-[4-{4-(4'-cyano-biphenyl-4-yl)-naphthalen-1-yl}-phenyl]-6-(phenanthrene-9-yl)-benzoxazole (Compound-138).

[0374] [Chemistry 40]

[0375]

[0376] The structure of the obtained yellow powder was identified using NMR.

[0377] use 1 The following 30 hydrogen signals were detected by H-NMR (CDCl3).

[0378] δ(ppm)=8.85(1H), 8.79(1H), 8.50(2H), 8.07(2H), 8.01(1H), 7.97(2H) ,7.87-7.75(10H),7.72(4H),7.67(1H),7.62(2H),7.59(2H),7.55(2H)

[0379] (Example 29)

[0380] <Synthesis of 4-(biphenyl-4-yl)-6-(4-cyano-phenyl)-2-([1,1';4',1"]terphenyl-4-yl)-benzoxazole (Compound-143)>

[0381] A reaction vessel was charged with 6-chloro-4-(biphenyl-4-yl)-6-([1,1'; 4',1"]terphenyl-4-yl)-benzoxazole: 6.0 g, 4-cyanophenylboronic acid: 2.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.3 g, tricyclohexylphosphine: 0.3 g, and tripotassium phosphate: 4.8 g, and the mixture was refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the mixture was dispersed, washed, and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a monochlorobenzene solvent to obtain 4-(biphenyl-4-yl)-6-(4-cyano-phenyl)-2-([1,1'; 4',1"]terphenyl-4-yl)-benzoxazole (Compound-143) as a light yellow powder: 3.5 g (yield: 52%).

[0382] [Chemistry 41]

[0383]

[0384] The structure of the obtained light yellow powder was identified using NMR.

[0385] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0386] δ(ppm)=8.44(2H), 8.24(2H), 7.89-7.65(18H), 7.52(4H), 7.42(2H)

[0387] (Example 30)

[0388] <Synthesis of 6-(4-cyano-phenyl)-4-(phenanthrene-9-yl)-2-{4-(phenanthrene-9-yl)-phenyl}-benzoxazole (Compound-144)>

[0389] 15.7 g of 6-chloro-4-(phenanthrene-9-yl)-2-{4-(phenanthrene-9-yl)-phenyl}-benzoxazole, 4.2 g of 4-cyanophenylboronic acid, 0.7 g of tris(dibenzylideneacetone)dipalladium(0), 0.8 g of tricyclohexylphosphine, and 11.5 g of tripotassium phosphate were placed in a reaction container and stirred under reflux overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, water was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a monochlorobenzene solvent to obtain 12.6 g (yield: 72%) of white powder of 6-(4-cyano-phenyl)-4-(phenanthrene-9-yl)-2-{4-(phenanthrene-9-yl)-phenyl}-benzoxazole (Compound-144).

[0390] [Chemistry 42]

[0391]

[0392] The structure of the obtained white powder was identified using NMR.

[0393] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0394] δ(ppm)=8.87(1H), 8.81(2H), 8.75(1H), 8.37(2H), 8.00(1H), 7.99-7.60(19H), 7.56(2H)

[0395] (Example 31)

[0396] <Synthesis of 2-(biphenyl-4-yl)-6-(4-cyano-phenyl)-4-(phenanthrene-9-yl)-benzoxazole (Compound-147)>

[0397] 2-(Biphenyl-4-yl)-6-chloro-4-(phenanthrene-9-yl)-benzoxazole: 10.5 g, 4-cyanophenylboronic acid: 3.8 g, tris(dibenzylideneacetone)dipalladium(0): 0.6 g, tricyclohexylphosphine: 0.6 g, tripotassium phosphate: 9.2 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using toluene solvent to obtain 7.2 g (yield: 60%) of white powder of 2-(biphenyl-4-yl)-6-(4-cyano-phenyl)-4-(phenanthrene-9-yl)-benzoxazole (Compound-147).

[0398] [Chemistry 43]

[0399]

[0400] The structure of the obtained white powder was identified using NMR.

[0401] use 1 The following 24 hydrogen signals were detected by H-NMR (CDCl3).

[0402] δ(ppm)=8.86(1H), 8.81(1H), 8.28(2H), 7.97(2H), 7.93(1H), 7.91-7.61(13H), 7.54(1H), 7.49(2H), 7.41(1H)

[0403] (Example 32)

[0404] <Synthesis of 2-(biphenyl-4-yl)-6-(4'-cyano-biphenyl-4-yl)-4-(phenanthrene-9-yl)-benzoxazole (Compound-148)>

[0405] 2-(Biphenyl-4-yl)-6-chloro-4-(phenanthrene-9-yl)-benzoxazole: 10.5 g, 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)biphenyl-4-carbonitrile: 8.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.6 g, tricyclohexylphosphine: 0.6 g, tripotassium phosphate: 9.2 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and dispersion washing and filtration were performed to obtain a crude product. The obtained crude product was purified by recrystallization using monochlorobenzene solvent to obtain 11.4 g (yield: 84%) of white powder of 2-(biphenyl-4-yl)-6-(4'-cyano-biphenyl-4-yl)-4-(phenanthrene-9-yl)-benzoxazole (Compound-148).

[0406] [Chemistry 44]

[0407]

[0408] The structure of the obtained white powder was identified using NMR.

[0409] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0410] δ(ppm)=8.87(1H), 8.82(1H), 8.30(2H), 8.00(3H), 7.94(1H), 7.88(2H) ), 7.84(1H), 7.78(4H), 7.77-7.63(9H), 7.55(1H), 7.49(2H), 7.41(1H)

[0411] (Example 33)

[0412] <Synthesis of 6-(4'-cyano-biphenyl-4-yl)-2-{4-(phenanthrene-9-yl)-phenyl}-4-phenyl-benzoxazole (Compound-149)>

[0413] 2-(4-chloro-phenyl)-6-(4'-cyano-biphenyl-4-yl)-4-phenyl-benzoxazole: 13.0 g, 9-phenanthrene boronic acid: 6.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.7 g, tricyclohexylphosphine: 0.8 g, tripotassium phosphate: 11.4 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a monochlorobenzene solvent to obtain 6-(4'-cyano-biphenyl-4-yl)-2-{4-(phenanthrene-9-yl)-phenyl}-4-phenyl-benzoxazole (Compound-149) as a white powder: 12.0 g (yield: 71%).

[0414] [Chemistry 45]

[0415]

[0416] The structure of the obtained white powder was identified using NMR.

[0417] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0418] δ(ppm)=8.82(1H), 8.78(1H), 8.50(2H), 8.18(2H), 7.98(1H), 7.95(1H) ,7.88(4H),7.81-7.71(11H),7.68(1H),7.64(1H),7.60(2H),7.50(1H)

[0419] (Example 34)

[0420] <Synthesis of 6-(4'-cyano-biphenyl-4-yl)-2-{4-(9,9'-spirobi[9H]fluoren-4-yl)-phenyl}-benzoxazole (Compound-150)>

[0421] 2-(4-chloro-phenyl)-6-(4'-cyano-biphenyl-4-yl)-benzoxazole: 11.3 g, 9,9'-spirobi[9H]fluorene-4-yl-boric acid: 11.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.8 g, tricyclohexylphosphine: 0.8 g, tripotassium phosphate: 11.8 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and dispersion washing and filtration were performed to obtain a crude product. The obtained crude product was purified by recrystallization using monochlorobenzene as a solvent to obtain 12.6 g (yield: 66%) of light yellow powder of 6-(4'-cyano-biphenyl-4-yl)-2-{4-(9,9'-spirobi[9H]fluoren-4-yl)-phenyl}-benzoxazole (Compound-150).

[0422] [Chemistry 46]

[0423]

[0424] The structure of the obtained light yellow powder was identified using NMR.

[0425] use 1 The following 30 hydrogen signals were detected by H-NMR (CDCl3).

[0426] δ(ppm)=8.51(2H), 7.94(1H), 7.92(1H), 7.91(1H), 7.88(2H), 7.84(3H), 7.80(2H), 7.79(3H), 7.7 5(1H), 7.73(1H), 7.42(2H), 7.27(1H), 7.22-7.14(4H), 7.07(2H), 6.85(2H), 6.79(1H), 6.74(1H)

[0427] (Example 35)

[0428] <Synthesis of 6-(4'-cyano-biphenyl-4-yl)-4-phenyl-2-{4-(9,9'-spirobi[9H]fluoren-4-yl)-phenyl}-benzoxazole (Compound-151)>

[0429] 2-(4-chloro-phenyl)-6-(4'-cyano-biphenyl-4-yl)-4-phenyl-benzoxazole: 12.1 g, 9,9'-spirobi[9H]fluorene-4-yl-boric acid: 6.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.7 g, tricyclohexylphosphine: 0.7 g, tripotassium phosphate: 10.6 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and dispersion washing and filtration were performed to obtain a crude product. The crude product was purified by recrystallization using monochlorobenzene as a solvent to obtain 8.2 g (yield: 43%) of light yellow powder of 6-(4'-cyano-biphenyl-4-yl)-4-phenyl-2-{4-(9,9'-spirobi[9H]fluoren-4-yl)-phenyl}-benzoxazole (Compound-151).

[0430] [Chemistry 47]

[0431]

[0432] The structure of the obtained light yellow powder was identified using NMR.

[0433] use 1 The following 34 hydrogen signals were detected by H-NMR (CDCl3).

[0434] δ(ppm)=8.55(2H), 8.19(2H), 7.94-7.85(7H), 7.85-7.74(6H), 7.63(2H), 7.51(1H), 7.42(2H), 7.27(1H), 7.28(1H), 7.18(4H), 7.07(2H), 6.86(2H), 6.79(1H), 6.75(1H)

[0435] (Example 36)

[0436] <Synthesis of 2-(biphenyl-4-yl)-6-{4-(4-cyano-phenyl)-naphthalen-1-yl}-4-phenyl-benzoxazole (Compound-154)>

[0437] 2-(Biphenyl-4-yl)-6-bromo-4-phenyl-benzooxazole: 13.2 g, 4-{4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-naphthalene-1-yl}-phenyl-carbonitrile: 11.5 g, tetrakis(triphenylphosphine)dipalladium(0): 0.7 g, potassium carbonate: 7.3 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of toluene, ethanol, and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The obtained crude product was purified by crystallization using a mixed solvent of tetrahydrofuran / acetone to obtain 2-(biphenyl-4-yl)-6-{4-(4-cyano-phenyl)-naphthalene-1-yl}-4-phenyl-benzooxazole (Compound-154) as a white powder: 15.8 g (yield: 89%).

[0438] [Chemistry 48]

[0439]

[0440] The structure of the obtained white powder was identified using NMR.

[0441] use 1 The following 26 hydrogen signals were detected by H-NMR (CDCl3).

[0442] δ(ppm)=8.46(2H), 8.18(2H), 8.14(1H), 7.91(1H), 7.86(2H), 7.81(2H), 7.76(2H), 7.72(4H), 7.65(1H), 7.62-7.40(9H)

[0443] (Example 37)

[0444] <Synthesis of 6-[4-{4-(4'-cyano-biphenyl-4-yl)-naphthalen-1-yl}-phenyl]-2,4-diphenyl-benzoxazole (Compound-155)>

[0445] 4.0 g of 6-chloro-2,4-diphenyl-benzoxazole, 5.9 g of 4'-{4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-naphthalene-1-yl}-biphenyl-4-carbonitrile, 0.4 g of tris(dibenzylideneacetone)dipalladium(0), 0.4 g of tricyclohexylphosphine, and 5.6 g of tripotassium phosphate were placed in a reaction container, and stirred under reflux overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using monochlorobenzene as a solvent to obtain 3.2 g (yield: 43%) of white powder of 6-[4-{4-(4'-cyano-biphenyl-4-yl)-naphthalen-1-yl}-phenyl]-2,4-diphenyl-benzoxazole (Compound-155).

[0446] [Chemistry 49]

[0447]

[0448] The structure of the obtained white powder was identified using NMR.

[0449] use 1 The following 26 hydrogen signals were detected by H-NMR (CDCl3).

[0450] δ(ppm)=8.40(1H), 8.38(1H), 8.17(2H), 8.13(1H), 8.07(1H), 7.83(5H), 7.77(3H), 7.72(2H), 7.67-7.51(9H), 7.47(1H)

[0451] (Example 38)

[0452] <Synthesis of 2-(biphenyl-4-yl)-6-(4"-cyano-[1,1';4',1"]terphenyl-4-yl)-4-phenyl-benzoxazole (Compound-156)>

[0453] In a reaction vessel, 13.2 g of 2-(biphenyl-4-yl)-6-bromo-4-phenyl-benzoxazole, 12.4 g of 4-(4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-[1,1';4',1"]terphenyl-4"-carbonitrile, 0.7 g of tetrakis(triphenylphosphine)dipalladium(0), and 7.3 g of potassium carbonate were added and dissolved in a mixed solution of toluene, ethanol, and H2O. Reflux with stirring overnight. After natural cooling, methanol is added to the system for dispersion, washing and filtration to obtain a crude product. The crude product is purified by recrystallization using monochlorobenzene solvent to obtain 2-(biphenyl-4-yl)-6-(4"-cyano-[1,1';4',1"]triphenyl-4-yl)-4-phenyl-benzoxazole (Compound-156) as a white powder: 7.2 g (yield: 39%).

[0454] [Chemistry 50]

[0455]

[0456] The structure of the obtained white powder was identified using NMR.

[0457] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0458] δ(ppm)=8.42(2H), 8.16(2H), 7.86(3H), 7.84(2H), 7.81(4H), 7.78(5H), 7.74(2H), 7.71(2H), 7.60(2H), 7.52(2H), 7.49(1H), 7.45(1H)

[0459] (Example 39)

[0460] <Synthesis of 2-{4-(phenanthrene-9-yl)-phenyl}-6-(4"-cyano-[1,1';4',1"]terphenyl-4-yl)-4-phenyl-benzoxazole (Compound-157)>

[0461] 2-(4-chloro-phenyl)-6-(4"-cyano-[1,1';4',1"]terphenyl-4-yl)-4-phenyl-benzoxazole: 12.8 g, 9-phenanthreneboric acid: 5.3 g, tris(dibenzylideneacetone)dipalladium(0): 0.6 g, tricyclohexylphosphine: 0.6 g, tripotassium phosphate: 9.7 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The crude product was purified by recrystallization using monochlorobenzene solvent to obtain 5.3 g (yield: 33%) of white powder of 2-{4-(phenanthrene-9-yl)-phenyl}-6-(4"-cyano-[1,1';4',1"]terphenyl-4-yl)-4-phenyl-benzoxazole (Compound-157).

[0462] [Chemistry 51]

[0463]

[0464] The structure of the obtained white powder was identified using NMR.

[0465] use 1 The following 32 hydrogen signals were detected by H-NMR (CDCl3).

[0466] δ(ppm)=8.84(1H), 8.78(1H), 8.50(2H), 8.19(2H), 7.97(2H), 7.91-7.66(20H), 7.61(3H), 7.49(1H)

[0467] (Example 40)

[0468] <Synthesis of 2-(biphenyl-4-yl)-6-(3"-cyano-[1,1';4',1"]terphenyl-4-yl)-4-phenyl-benzoxazole (Compound-158)>

[0469] A reaction vessel was charged with 2-(biphenyl-4-yl)-6-chloro-4-phenyl-benzoxazole: 11.0 g, 4-(4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-[1,1';4',1"]terphenyl-3"-carbonitrile: 11.5 g, tris(dibenzylideneacetone)dipalladium(0): 0.8 g, tricyclohexylphosphine: 0.8 g, and tripotassium phosphate: 12.2 g. In 1,4-dioxane, Reflux with stirring under H2O mixed solvent for one night. After natural cooling, methanol is added into the system for dispersion, washing and filtration to obtain a crude product. The obtained crude product is purified by recrystallization using 1,2-dichlorobenzene solvent to obtain 2-(biphenyl-4-yl)-6-(3"-cyano-[1,1';4',1"]triphenyl-4-yl)-4-phenyl-benzoxazole (Compound-158) as a light yellow powder: 15.4 g (yield: 89%).

[0470] [Chemistry 52]

[0471]

[0472] The structure of the obtained light yellow powder was identified using NMR.

[0473] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0474] δ(ppm)=8.42(2H), 8.17(2H), 7.96(1H), 7.90(1H), 7.88-7.76(10H), 7.74-7.66(5H), 7.60(3H), 7.54(2H), 7.45(2H)

[0475] (Example 41)

[0476] <Synthesis of 2-(biphenyl-4-yl)-6-{4-(4'-cyano-biphenyl-4-yl)-naphthalen-1-yl}-4-phenyl-benzoxazole (Compound-159)>

[0477] 2-(Biphenyl-4-yl)-6-bromo-4-phenyl-benzoxazole: 13.2 g, 4'-{4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-naphthalene-1-yl}-biphenyl-4-carbonitrile: 14.0 g, tetrakis(triphenylphosphine)dipalladium(0): 0.7 g, potassium carbonate: 7.3 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of toluene, ethanol, and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The obtained crude product was purified by crystallization using a tetrahydrofuran / acetone mixed solvent to obtain 13.0 g (yield: 65%) of white powder of 2-(biphenyl-4-yl)-6-{4-(4'-cyano-biphenyl-4-yl)-naphthalen-1-yl}-4-phenyl-benzoxazole (Compound-159).

[0478] [Chemistry 53]

[0479]

[0480] The structure of the obtained white powder was identified using NMR.

[0481] use 1 The following 30 hydrogen signals were detected by H-NMR (CDCl3).

[0482] δ(ppm)=8.46(2H), 8.19(2H), 8.15(1H), 8.08(1H), 7.87-7.77(10H), 7.72(4H), 7.66(1H), 7.62-7.41(9H)

[0483] (Example 42)

[0484] <Synthesis of 2-(biphenyl-4-yl)-6-{2-(4'-cyano-biphenyl-4-yl)-naphthalen-6-yl}-4-phenyl-benzoxazole (Compound-160)>

[0485] A reaction vessel was charged with 2-(biphenyl-4-yl)-6-chloro-4-phenyl-benzoxazole: 13.2 g, 4'-{2-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-naphthalene-6-yl}-biphenyl-4-carbonitrile: 15.7 g, tris(dibenzylideneacetone)dipalladium(0): 0.9 g, tricyclohexylphosphine: 1.0 g, and tripotassium phosphate: 14.7 g, and the mixture was refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the mixture was dispersed, washed, and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using 1,2-dichlorobenzene solvent to obtain 17.0 g (yield: 72%) of light yellow powder of 2-(biphenyl-4-yl)-6-{2-(4'-cyano-biphenyl-4-yl)-naphthalen-6-yl}-4-phenyl-benzoxazole (Compound-160).

[0486] [Chemistry 54]

[0487]

[0488] The structure of the obtained light yellow powder was identified using NMR.

[0489] use 1 The following 30 hydrogen signals were detected by H-NMR (CDCl3).

[0490] δ(ppm)=8.43(2H), 8.22(2H), 8.18(2H), 8.08(2H), 7.97(2H), 7.93(3H), 7.8 8(1H), 7.85-7.77(7H), 7.75(2H), 7.70(1H), 7.61(2H), 7.52(3H), 7.45(1H)

[0491] (Example 43)

[0492] <Synthesis of 2-(biphenyl-4-yl)-6-{2-(4'-cyano-biphenyl-4-yl)-naphthalen-7-yl}-4-phenyl-benzoxazole (Compound-161)>

[0493] A reaction vessel was charged with 2-(biphenyl-4-yl)-6-chloro-4-phenyl-benzoxazole: 13.2 g, 4'-{2-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-naphthalene-7-yl}-biphenyl-4-carbonitrile: 15.7 g, tris(dibenzylideneacetone)dipalladium(0): 0.9 g, tricyclohexylphosphine: 1.0 g, and tripotassium phosphate: 14.7 g, and the mixture was refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the mixture was dispersed, washed, and filtered to obtain a crude product. The crude product was purified by recrystallization using 1,2-dichlorobenzene as a solvent to obtain 17.3 g (yield: 77%) of light yellow powder of 2-(biphenyl-4-yl)-6-{2-(4'-cyano-biphenyl-4-yl)-naphthalen-7-yl}-4-phenyl-benzoxazole (Compound-161).

[0494] [Chemistry 55]

[0495]

[0496] The structure of the obtained light yellow powder was identified using NMR.

[0497] use 1 The following 30 hydrogen signals were detected by H-NMR (CDCl3).

[0498] δ(ppm)=8.42(2H), 8.23(2H), 8.19(2H), 8.03(2H), 7.94(2H), 7.92(3H), 7.84(2H ), 7.82-7.76(6H), 7.73(2H), 7.70(1H), 7.61(2H), 7.52(2H), 7.51(1H), 7.45(1H)

[0499] (Example 44)

[0500] <Synthesis of 2-(biphenyl-4-yl)-4-(4-cyano-phenyl)-6-(phenanthrene-9-yl)-benzoxazole (Compound-164)>

[0501] 9.4 g of 2-(4-chloro-phenyl)-4-(4-cyano-phenyl)-6-(phenanthrene-9-yl)-benzoxazole, 2.4 g of phenylboric acid, 0.5 g of tris(dibenzylideneacetone)dipalladium(0), 0.5 g of tricyclohexylphosphine, and 7.9 g of tripotassium phosphate were placed in a reaction container and refluxed with stirring overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The obtained crude product was purified by crystallization using a mixed solvent of toluene / acetone to obtain 5.3 g (yield: 51%) of white powder of 2-(biphenyl-4-yl)-4-(4-cyano-phenyl)-6-(phenanthrene-9-yl)-benzoxazole (Compound-164).

[0502] [Chemistry 56]

[0503]

[0504] The structure of the obtained white powder was identified using NMR.

[0505] use 1 The following 24 hydrogen signals were detected by H-NMR (CDCl3).

[0506] δ(ppm)=8.86(1H), 8.80(1H), 8.45(2H), 8.33(2H), 8.01(1H), 7.96(1H), 7.90-7.65(12H), 7.61(1H), 7.54(2H), 7.46(1H)

[0507] (Example 45)

[0508] <Synthesis of 2-(biphenyl-4-yl)-4-(3-cyano-phenyl)-6-(phenanthrene-9-yl)-benzoxazole (Compound-165)>

[0509] 2-(Biphenyl-4-yl)-6-chloro-4-(3-cyano-phenyl)-benzoxazole: 9.1 g, 9-phenanthrene boronic acid: 6.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.6 g, tricyclohexylphosphine: 0.6 g, tripotassium phosphate: 9.5 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a monochlorobenzene solvent to obtain 2-(biphenyl-4-yl)-4-(3-cyano-phenyl)-6-(phenanthrene-9-yl)-benzoxazole (Compound-165) as a white powder: 10.4 g (yield: 85%).

[0510] [Chemistry 57]

[0511]

[0512] The structure of the obtained white powder was identified using NMR.

[0513] use 1 The following 24 hydrogen signals were detected by H-NMR (CDCl3).

[0514] δ(ppm)=8.86(1H), 8.79(1H), 8.59(1H), 8.45(2H), 8.38(1H), 8.02(1H) ), 7.97(1H), 7.84(2H), 7.83(2H), 7.79-7.53(9H), 7.54(2H), 7.45(1H)

[0515] (Example 46)

[0516] <Synthesis of 2-(biphenyl-4-yl)-4-(4-cyano-phenyl)-6-{4-(phenanthrene-9-yl)-phenyl}-benzoxazole (Compound-166)>

[0517] 2-(Biphenyl-4-yl)-6-chloro-4-(4-cyano-phenyl)-benzoxazole: 9.0 g, 4-(phenanthrene-9-yl)phenylboronic acid: 7.9 g, tris(dibenzylideneacetone)dipalladium(0): 0.6 g, tricyclohexylphosphine: 0.6 g, tripotassium phosphate: 9.4 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a monochlorobenzene solvent to obtain 2-(biphenyl-4-yl)-4-(4-cyano-phenyl)-6-{4-(phenanthrene-9-yl)-phenyl}-benzoxazole (Compound-166) as a white powder: 11.7 g (yield: 85%).

[0518] [Chemistry 58]

[0519]

[0520] The structure of the obtained white powder was identified using NMR.

[0521] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0522] δ(ppm)=8.85(1H), 8.78(1H), 8.44(2H), 8.34(2H)8.05(1H), 7.96(3H), 7.89(4H) ,7.83(2H),7.79(1H),7.77-7.68(6H),7.66(1H),7.62(1H),7.53(2H),7.45(1H)

[0523] (Example 47)

[0524] <Synthesis of 2-(biphenyl-4-yl)-4-(3-cyano-phenyl)-6-{4-(phenanthrene-9-yl)-phenyl}-benzoxazole (Compound-167)>

[0525] 2-(Biphenyl-4-yl)-6-chloro-4-(3-cyano-phenyl)-benzoxazole: 9.1 g, 4-(phenanthrene-9-yl)phenylboronic acid: 8.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.6 g, tricyclohexylphosphine: 0.6 g, tripotassium phosphate: 9.5 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a monochlorobenzene solvent to obtain 2-(biphenyl-4-yl)-4-(3-cyano-phenyl)-6-{4-(phenanthrene-9-yl)-phenyl}-benzoxazole (Compound-167) as a white powder: 11.9 g (yield: 85%).

[0526] [Chemistry 59]

[0527]

[0528] The structure of the obtained white powder was identified using NMR.

[0529] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0530] δ(ppm)=8.84(1H), 8.78(1H), 8.56(1H), 8.43(3H), 8.05(1H), 7.97(1H), 7.9 6(1H), 7.90(2H), 7.85(2H), 7.82-7.68(10H), 7.63(2H), 7.53(2H), 7.45(1H)

[0531] (Example 48)

[0532] <Synthesis of 2-(biphenyl-4-yl)-4-(4'-cyano-biphenyl-4-yl)-6-(phenanthrene-9-yl)-benzoxazole (Compound-168)>

[0533] 9.4 g of 2-(4-chloro-phenyl)-4-(4'-cyano-biphenyl-4-yl)-6-(phenanthrene-9-yl)-benzoxazole, 2.1 g of phenylboric acid, 0.4 g of tris(dibenzylideneacetone)dipalladium(0), 0.5 g of tricyclohexylphosphine, and 6.8 g of tripotassium phosphate were placed in a reaction container and refluxed with stirring overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using a monochlorobenzene solvent to obtain 5.2 g (yield: 51%) of white powder of 2-(biphenyl-4-yl)-4-(4'-cyano-biphenyl-4-yl)-6-(phenanthrene-9-yl)-benzoxazole (Compound-168).

[0534] [Chemistry 60]

[0535]

[0536] The structure of the obtained white powder was identified using NMR.

[0537] use 1 The following 28 hydrogen signals were detected by H-NMR (CDCl3).

[0538] δ(ppm)=8.86(1H), 8.80(1H), 8.46(2H), 8.32(2H), 8.07(1H), 7.96(1H), 7.88-7.77(11H), 7.77-7.65(5H), 7.61(1H), 7.53(2H), 7.45(1H).

[0539] (Example 49)

[0540] <Synthesis of 2-(biphenyl-4-yl)-6-(4'-cyano-biphenyl-4-yl)-4-{4-(pyridin-3-yl)-phenyl}-benzoxazole (Compound-173)>

[0541] 7.5 g of 2-(biphenyl-4-yl)-6-chloro-4-{4-(pyridin-3-yl)-phenyl}-benzoxazole, 5.5 g of 4'-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolane-2-yl)biphenyl-4-carbonitrile, 0.8 g of tris(dibenzylideneacetone)dipalladium(0), 0.9 g of tricyclohexylphosphine, and 10.4 g of tripotassium phosphate were placed in a reaction container, and the mixture was stirred under reflux overnight in a mixed solvent of 1,4-dioxane and H2O. After cooling naturally, water was added to the system, and the mixture was dispersed, washed, and filtered to obtain a crude product. The crude product was purified by crystallization using a mixed solvent of N-methylpyrrolidone / acetone to obtain 6.5 g (yield: 66%) of light yellow powder of 2-(biphenyl-4-yl)-6-(4'-cyano-biphenyl-4-yl)-4-{4-(pyridin-3-yl)-phenyl}-benzoxazole (Compound-173).

[0542] [Chemistry 61]

[0543]

[0544] The structure of the obtained light yellow powder was identified using NMR.

[0545] use 1 The following 27 hydrogen signals were detected by H-NMR (CDCl3).

[0546] δ(ppm)=9.00(1H), 8.67(1H), 8.43(2H), 8.29(2H), 8.01(1H), 7.92-7.73(14H), 7.72(2H), 7.53(2H), 7.44(2H)

[0547] (Example 50)

[0548] <Synthesis of 6-(4'-cyano-biphenyl-4-yl)-4-phenyl-2-{4'-(pyridin-3-yl)-biphenyl-4-yl}-benzoxazole (Compound-175)>

[0549] 2-(4-chloro-phenyl)-6-(4'-cyano-biphenyl-4-yl)-4-phenyl-benzoxazole: 16.3 g, 4-(pyridin-3-yl)phenylboronic acid: 7.1 g, tris(dibenzylideneacetone)dipalladium(0): 0.6 g, tricyclohexylphosphine: 0.4 g, tripotassium phosphate: 12.2 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using 1,2-dichlorobenzene solvent to obtain 6-(4'-cyano-biphenyl-4-yl)-4-phenyl-2-{4'-(pyridin-3-yl)-biphenyl-4-yl}-benzoxazole (Compound-175) as a light yellow powder: 19.4 g (yield: 96%).

[0550] [Chemistry 62]

[0551]

[0552] The structure of the obtained light yellow powder was identified using NMR.

[0553] use 1 The following 27 hydrogen signals were detected by H-NMR (CDCl3).

[0554] δ(ppm)=8.95(1H), 8.66(1H), 8.44(2H), 8.15(2H), 7.92(1H), 7.89-7.70(16H), 7.61(2H), 7.49(1H), 7.43(1H)

[0555] (Example 51)

[0556] <Synthesis of 2-(biphenyl-4-yl)-4-(4'-cyano-biphenyl-4-yl)-6-{4-(pyridin-3-yl)-phenyl}-benzoxazole (Compound-179)>

[0557] 2-(Biphenyl-4-yl)-6-chloro-4-(4'-cyano-biphenyl-4-yl)-benzoxazole: 11.8 g, 4-(pyridin-3-yl)phenylboronic acid: 5.1 g, tris(dibenzylideneacetone)dipalladium(0): 0.7 g, tricyclohexylphosphine: 0.7 g, tripotassium phosphate: 10.3 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, methanol was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The obtained crude product was purified by crystallization using a monochlorobenzene / acetone mixed solvent to obtain 10.5 g (yield: 72%) of light yellow powder of 2-(biphenyl-4-yl)-4-(4'-cyano-biphenyl-4-yl)-6-{4-(pyridin-3-yl)-phenyl}-benzoxazole (Compound-179).

[0558] [Chemistry 63]

[0559]

[0560] The structure of the obtained light yellow powder was identified using NMR.

[0561] use 1 The following 27 hydrogen signals were detected by H-NMR (CDCl3).

[0562] δ(ppm)=8.97(1H), 8.66(1H), 8.41(2H), 8.28(2H), 7.97(1H), 7.91-7.66(16H), 7.52(2H), 7.44(2H)

[0563] (Example 52)

[0564] <Synthesis of 2-(biphenyl-4-yl)-4-(4'-cyano-biphenyl-3-yl)-6-{4-(pyridin-3-yl)-phenyl}-benzoxazole (Compound-180)>

[0565] 2-(Biphenyl-4-yl)-6-chloro-4-(4'-cyano-biphenyl-3-yl)-benzoxazole: 5.0 g, 4-(pyridin-3-yl)phenylboronic acid: 2.3 g, tris(dibenzylideneacetone)dipalladium(0): 0.2 g, tricyclohexylphosphine: 0.3 g, tripotassium phosphate: 6.6 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, water was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by recrystallization using 1,2-dichlorobenzene solvent to obtain 2-(biphenyl-4-yl)-4-(4'-cyano-biphenyl-3-yl)-6-{4-(pyridin-3-yl)-phenyl}-benzoxazole (Compound-180) as a light yellow powder: 5.4 g (yield: 87%).

[0566] [Chemistry 64]

[0567]

[0568] The structure of the obtained light yellow powder was identified using NMR.

[0569] use 1 The following 27 hydrogen signals were detected by H-NMR (CDCl3).

[0570] δ(ppm)=8.96(1H), 8.67(1H), 8.41(1H), 8.39(2H), 8.19(1H), 7.98(1H), 7.92-7.74(11H), 7.71(5H), 7.53(2H), 7.44(2H)

[0571] (Example 53)

[0572] <Synthesis of 2-(biphenyl-4-yl)-4-(3'-cyano-biphenyl-4-yl)-6-{4-(pyridin-3-yl)-phenyl}-benzoxazole (Compound-181)>

[0573] 2-(Biphenyl-4-yl)-6-chloro-4-(3'-cyano-biphenyl-4-yl)-benzoxazole: 6.0 g, 4-(pyridin-3-yl)phenylboronic acid: 3.0 g, tris(dibenzylideneacetone)dipalladium(0): 0.3 g, tricyclohexylphosphine: 0.4 g, tripotassium phosphate: 7.9 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, water was added to the system, and the system was dispersed, washed and filtered to obtain a crude product. The obtained crude product was purified by crystallization using a mixed solvent of monochlorobenzene / acetone to obtain 5.2 g (yield: 70%) of a light yellow powder of 2-(biphenyl-4-yl)-4-(3'-cyano-biphenyl-4-yl)-6-{4-(pyridin-3-yl)-phenyl}-benzoxazole (Compound-181).

[0574] [Chemistry 65]

[0575]

[0576] The structure of the obtained light yellow powder was identified using NMR.

[0577] use 1 The following 27 hydrogen signals were detected by H-NMR (CDCl3).

[0578] δ(ppm)=8.92(1H), 8.67(1H), 8.43(2H), 8.29(2H), 8.00(1H), 7.95(2H) ), 7.88(3H), 7.84-7.73(6H), 7.70(3H), 7.64(2H), 7.53(2H), 7.45(2H)

[0579] (Example 54)

[0580] <Synthesis of 2-(biphenyl-4-yl)-4-(4'-cyano-biphenyl-4-yl)-6-{4-(pyridin-2-yl)-phenyl}-benzoxazole (Compound-182)>

[0581] 2-(Biphenyl-4-yl)-6-chloro-4-(4'-cyano-biphenyl-4-yl)-benzoxazole: 6.0 g, 2-{4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl}-pyridine: 4.2 g, tris(dibenzylideneacetone)dipalladium(0): 0.3 g, tricyclohexylphosphine: 0.4 g, tripotassium phosphate: 7.9 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of 1,4-dioxane and H2O. After natural cooling, water was added to the system, and the system was dispersed, washed, and filtered to obtain a crude product. The obtained crude product was purified by crystallization using a monochlorobenzene / acetone mixed solvent to obtain 5.4 g (yield: 72%) of light yellow powder of 2-(biphenyl-4-yl)-4-(4'-cyano-biphenyl-4-yl)-6-{4-(pyridin-2-yl)-phenyl}-benzoxazole (Compound-182).

[0582] [Chemistry 66]

[0583]

[0584] The structure of the obtained light yellow powder was identified using NMR.

[0585] use 1 The following 27 hydrogen signals were detected by H-NMR (CDCl3).

[0586] δ(ppm)=8.77(1H), 8.42(2H), 8.30(2H), 8.18(2H), 7.92-7.73(13H), 7.70(3H), 7.52(2H), 7.45(1H), 7.31(1H)

[0587] (Example 55)

[0588] <Synthesis of 2-[4-{7-(4'-cyano-biphenyl-4-yl)-9,9-diphenyl-9H-fluoren-2-yl}-phenyl]-benzoxazole (Compound-201)>

[0589] 2-{4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl}-benzoxazole: 2.8 g, 4'-(7-bromo-9,9-diphenyl-9H-fluorene-2-yl)-biphenyl-4-carbonitrile: 4.5 g, tetrakis(triphenylphosphine)dipalladium(0): 0.5 g, potassium carbonate: 1.6 g were placed in a reaction container, and refluxed and stirred overnight in a mixed solvent of toluene, ethanol, and H2O. After natural cooling, methanol was added to the system, and dispersion washing and filtration were performed to obtain a crude product. The obtained crude product was purified by recrystallization using monochlorobenzene as a solvent to obtain 5.0 g (yield: 93%) of yellow powder of 2-[4-{7-(4'-cyano-biphenyl-4-yl)-9,9-diphenyl-9H-fluoren-2-yl}-phenyl]-benzoxazole (Compound-201).

[0590] [Chemistry 67]

[0591]

[0592] The structure of the obtained yellow powder was identified using NMR.

[0593] use 1 The following 32 hydrogen signals were detected by H-NMR (CDCl3).

[0594] δ(ppm)=8.33(2H), 7.93(2H), 7.84-7.59(16H), 7.44-7.23(12H)

[0595] (Example 56)

[0596] The melting points and glass transition temperatures of the compounds having a benzoazole ring structure obtained in Examples 1 to 55 were measured using a high-sensitivity differential scanning calorimeter (DSC3100SA, manufactured by Bruker EcoScience).

[0597] [Table 1]

[0598]

[0599] The compounds having a benzoxazole ring structure obtained in Examples 1 to 55 have a glass transition temperature of 98° C. or higher, indicating that the thin film state is stable.

[0600] (Example 57)

[0601] The compounds having a benzoxazole ring structure obtained in Examples 1 to 55 were used to form a 100 nm thick vapor-deposited film on an ITO substrate, and the work function was measured using an ionization potential measuring device (PYS-202 manufactured by Sumitomo Heavy Industries, Ltd.).

[0602] [Table 2]

[0603]

[0604] The compounds having a benzoxazole ring structure obtained in Examples 1 to 55 have a work function greater than 5.5 eV of a general hole transport material such as NPD and TPD, and have a large hole blocking ability.

[0605] (Example 58)

[0606] As for organic EL elements, Fig.15 As shown in the figure, an ITO electrode is formed on a glass substrate 1 as a transparent anode 2, and then a hole injection layer 3, a hole transport layer 4, a light-emitting layer 5, a hole blocking layer 6, an electron transport layer 7, an electron injection layer 8, and a cathode (aluminum electrode) 9 are sequentially evaporated to produce it.

[0607] Specifically, a glass substrate 1 having an ITO film with a thickness of 50 nm formed thereon as a transparent anode 2 was ultrasonically cleaned in isopropyl alcohol for 20 minutes and then dried on a hot plate heated to 200°C for 10 minutes. After UV ozone treatment for 15 minutes, the glass substrate with ITO was placed in a vacuum deposition machine and the pressure was reduced to below 0.001 Pa. Next, as a hole injection layer 3, an electron acceptor (acceptor-1) of the following structural formula and a compound (HTM-1) of the following structural formula were binary deposited at a deposition rate ratio of acceptor-1:HTM-1=3:97 to cover the transparent anode 2, and the film thickness was 10 nm.

[0608] On the hole injection layer 3 , as the hole transport layer 4 , a compound (HTM-1) having the following structural formula was formed so as to have a film thickness of 60 nm.

[0609] On the hole transport layer 4, as the light-emitting layer 5, a compound of the following structural formula (EMD-1) and a compound of the following structural formula (EMH-1) are binary deposited at a deposition rate ratio of EMD-1:EMH-1=5:95 to form a film with a thickness of 20 nm.

[0610] On the light-emitting layer 5, as hole blocking layers and electron transport layers 6 and 7, the compound of Example 1 (Compound-2) and the compound of the following structural formula (ETM-1) are binary evaporated at a evaporation rate ratio of Compound-2:ETM-1=50:50 to form a film with a thickness of 30nm.

[0611] On the hole blocking layer / electron transporting layer 6 and 7, lithium fluoride was formed as the electron injecting layer 8 so as to have a film thickness of 1 nm.

[0612] Finally, aluminum was evaporated to a thickness of 100 nm to form the cathode 9 .

[0613] The characteristics of the organic EL elements produced were measured in the atmosphere at room temperature. Tables 3 and 4 show the results of the measurement of the light emission characteristics when a direct current voltage was applied to the organic EL elements produced.

[0614] [Chemistry 68]

[0615]

[0616] (Examples 59 to 112)

[0617] In Example 58, as the material for the hole blocking layer and electron transport layer 6 and 7, the compound of Example 2 to 55 was used instead of the compound of Example 1 (Compound-2), and binary evaporation was performed at an evaporation rate ratio of Compounds of Example 2 to 55: ETM-1 = 50:50, and the organic EL element was prepared under the same conditions. The characteristics of the prepared organic EL element were measured in the atmosphere at room temperature. The results of the measurement of the luminescent characteristics when a DC voltage was applied to the prepared organic EL element are summarized in Tables 3 and 4.

[0618] (Comparative Example 1)

[0619] For comparison, in Example 58, as the material for the hole blocking layer and electron transport layer 6 and 7, the compound (ETM-2) of the following structural formula (for example, refer to Patent Document 8) was used instead of the compound (Compound-2) of Example 1, and binary evaporation was performed at an evaporation rate ratio of ETM-2:ETM-1=50:50, and the organic EL element was produced under the same conditions. The characteristics of the produced organic EL element were measured in the atmosphere at room temperature. The results of the measurement of the luminescent characteristics when a DC voltage was applied to the produced organic EL element are summarized in Tables 3 and 4.

[0620] [Chemistry 69]

[0621]

[0622] (Comparative Example 2)

[0623] For comparison, in Example 58, as the material for the hole blocking layer and electron transport layer 6 and 7, the compound (ETM-3) of the following structural formula (for example, refer to Patent Document 9) was used instead of the compound (Compound-5) of Example 1, and binary evaporation was performed at an evaporation rate ratio of ETM-3:ETM-1=50:50, and the organic EL element was prepared under the same conditions. The characteristics of the prepared organic EL element were measured in the atmosphere at room temperature. The results of the measurement of the luminescent characteristics when a DC voltage was applied to the prepared organic EL element are summarized in Tables 3 and 4.

[0624] [Chemistry 70]

[0625]

[0626] The results of measuring the device life using the organic EL devices prepared in Examples 58 to 112 and Comparative Examples 1 and 2 are summarized in Tables 3 and 4. The device life was calculated when the luminance at the start of light emission (initial luminance) was 2000 cd / m 2 When driven with constant current, the luminance decays to 1900cd / m 2 The time for the initial brightness to decay to 95% (corresponding to 95% attenuation when the initial brightness is 100%) is measured.

[0627] [Table 3]

[0628]

[0629] [Table 4]

[0630]

[0631] As shown in Table 3 and Table 4, the current density is 10 mA / cm 2As for the driving voltage when the current flows, the organic EL element of Comparative Example 1 using the compound ETM-2 of the above structural formula and the organic EL element of Comparative Example 2 using the compound ETM-3 of the above structural formula are 3.82 to 4.01 V, and the organic EL elements of Examples 58 to 112 are 3.35 to 3.71 V, which is a lower voltage. In addition, in terms of luminous efficiency, the organic EL elements of Comparative Examples 1 and 2 are 6.59 to 8.05 cd / A, while the organic EL elements of Examples 58 to 112 are improved to 8.22 to 9.10 cd / A. In terms of power efficiency, the organic EL elements of Comparative Examples 1 and 2 are 5.16 to 6.62 lm / W, while the organic EL elements of Examples 58 to 112 are greatly improved to 7.13 to 8.34 lm / W. In particular, the device life (95% attenuation) was 165 to 203 hours in the organic EL devices of Comparative Examples 1 and 2, whereas it was 240 to 308 hours in the organic EL devices of Examples 58 to 112, which was significantly longer.

[0632] Therefore, it was found that the organic EL element of the present invention has excellent luminous efficiency and power efficiency compared with the elements using the compounds ETM-2 and ETM-3 of the above structural formulas, and can realize an organic EL element with a long life.

[0633] Industrial Applicability

[0634] The compound of the present invention having a specific benzoxazole ring structure has good electron injection characteristics, excellent hole blocking ability, and a stable film state, and is therefore excellent as a compound for an organic EL element. By using the compound to make an organic EL element, high efficiency can be obtained, and the driving voltage can be reduced, and durability can be improved. For example, it can be developed for use in household electrical products and lighting.

Claims

1. A compound having a benzoxazole ring structure, which is represented by the following general formula (a-5), In the formula, R may be the same as or different from each other, and represents a group represented by the following structural formula (b-1), a hydrogen atom, or a group selected from phenyl, naphthyl, phenanthryl, spirobifluorenyl, pyridyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted triazine, and a group composed of these groups and phenylene groups, However, at least one R is a group represented by the following structural formula (b-1), and at least one R is a group selected from phenyl, naphthyl, phenanthrenyl, spirobifluorenyl, pyridyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted triazine, and a group formed by combining these groups with phenylene. -LL2—(CN)nb1 In the formula, L1 represents a single bond or a group selected from unsubstituted phenylene, unsubstituted biphenylene, unsubstituted naphthylene and substituted or unsubstituted fluorenylene, L2 represents unsubstituted phenylene or unsubstituted biphenylene, n is an integer 1, The dotted line indicates the bonding site.

2. An organic electroluminescent element, comprising a pair of electrodes and at least one organic layer sandwiched therebetween, wherein: The invention comprises at least one organic layer comprising the compound having a benzoxazole ring structure according to claim 1.

3. The organic electroluminescent element according to claim 2, wherein: The organic layer using the compound having a benzoxazole ring structure is an electron transport layer.

4. The organic electroluminescent element according to claim 2, wherein: The organic layer using the compound having a benzoxazole ring structure is a hole blocking layer.

5. The organic electroluminescent element according to claim 2, wherein: The organic layer using the compound having a benzoxazole ring structure is a light-emitting layer.

6. The organic electroluminescent element according to claim 2, wherein: The organic layer using the compound having a benzoxazole ring structure is an electron injection layer.

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